admin_dashboard.php

<?php
include 'includes/db.php';
include 'includes/header.php';

// Check if user is logged in as admin
if (!isset($_SESSION['user_id']) || $_SESSION['role'] !== 'admin') {
    header('Location: login.php?type=admin');
    exit();
}

// Check for session messages
if (isset($_SESSION['success_message'])) {
    $success_message = $_SESSION['success_message'];
    unset($_SESSION['success_message']);
}

if (isset($_SESSION['error_message'])) {
    $error_message = $_SESSION['error_message'];
    unset($_SESSION['error_message']);
}

// Enable error reporting for debugging
ini_set('display_errors', 1);
error_reporting(E_ALL);


// ====== NEW: Set HOD ======
if (isset($_POST['set_hod'])) {
    $selectedId = isset($_POST['hod_faculty_id']) && $_POST['hod_faculty_id'] !== 'none' ? intval($_POST['hod_faculty_id']) : null;

    try {
        // Clear existing HOD
        $pdo->beginTransaction();
        $pdo->exec("UPDATE faculty SET is_hod = 0");

        if ($selectedId) {
            $stmt = $pdo->prepare("UPDATE faculty SET is_hod = 1 WHERE id = ?");
            $stmt->execute([$selectedId]);
        }

        $pdo->commit();
        $_SESSION['success_message'] = "HOD updated successfully.";
    } catch (Exception $e) {
        $pdo->rollBack();
        $_SESSION['error_message'] = "Failed to update HOD.";
        error_log("Set HOD error: " . $e->getMessage());
    }

    header("Location: admin_dashboard.php#manage-hod");
    exit();
}

// ====== NEW: Set Counsellor ======
if (isset($_POST['set_counsellor'])) {
    $selectedId = isset($_POST['counsellor_faculty_id']) && $_POST['counsellor_faculty_id'] !== 'none' ? intval($_POST['counsellor_faculty_id']) : null;

    try {
        // Clear existing Counsellor
        $pdo->beginTransaction();
        $pdo->exec("UPDATE faculty SET is_counsellor = 0");

        if ($selectedId) {
            $stmt = $pdo->prepare("UPDATE faculty SET is_counsellor = 1 WHERE id = ?");
            $stmt->execute([$selectedId]);
        }

        $pdo->commit();
        $_SESSION['success_message'] = "Counsellor updated successfully.";
    } catch (Exception $e) {
        $pdo->rollBack();
        $_SESSION['error_message'] = "Failed to update Counsellor.";
        error_log("Set Counsellor error: " . $e->getMessage());
    }

    header("Location: admin_dashboard.php#manage-counsellor");
    exit();
}

// Handle form submissions
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    // Add Announcement
    if (isset($_POST['add_announcement'])) {
        $title = $_POST['title'];
        $message = $_POST['message'];
        $stmt = $pdo->prepare("INSERT INTO announcements (title, message) VALUES (?, ?)");
        $stmt->execute([$title, $message]);
        $success_message = "Announcement added successfully.";
    }

    // Update Announcement
    if (isset($_POST['update_announcement'])) {
        $announcement_id = $_POST['announcement_id'];
        $title = $_POST['title'];
        $message = $_POST['message'];
        $stmt = $pdo->prepare("UPDATE announcements SET title=?, message=? WHERE id=?");
        $stmt->execute([$title, $message, $announcement_id]);
        $success_message = "Announcement updated successfully.";
        header("Location: admin_dashboard.php#manage-announcements");
        exit();
    }

    // Add Achievement image
    if (isset($_POST['add_achievement'])) {
        if (isset($_FILES['achievement_image']) && $_FILES['achievement_image']['error'] === UPLOAD_ERR_OK) {
            $upload_dir = 'assets/uploads/achievements/';
            if (!is_dir($upload_dir)) mkdir($upload_dir, 0755, true);

            $original = $_FILES['achievement_image']['name'];
            $ext = strtolower(pathinfo($original, PATHINFO_EXTENSION));
            $allowed = ['jpg', 'jpeg', 'png', 'gif', 'webp'];
            if (!in_array($ext, $allowed)) {
                $error_message = "Invalid file type for achievement image. Allowed: " . implode(', ', $allowed);
            } else {
                $filename = uniqid('ach_') . '.' . $ext;
                $target = $upload_dir . $filename;
                if (move_uploaded_file($_FILES['achievement_image']['tmp_name'], $target)) {
                    // Create table if not exists then insert record
                    $pdo->exec("CREATE TABLE IF NOT EXISTS achievements (
                        id INT AUTO_INCREMENT PRIMARY KEY,
                        file_path VARCHAR(255) NOT NULL,
                        alt_text VARCHAR(255) DEFAULT '',
                        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
                    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;");
                    $stmt = $pdo->prepare("INSERT INTO achievements (file_path, alt_text) VALUES (?, ?)");
                    $stmt->execute([$target, trim($_POST['alt_text'] ?? '')]);
                    $success_message = "Achievement image uploaded successfully.";
                } else {
                    $error_message = "Failed to move uploaded achievement image.";
                }
            }
        } else {
            $error_message = "No achievement image uploaded or upload error.";
        }
    }

    // Add Faculty
    if (isset($_POST['add_faculty'])) {
        $full_name = $_POST['full_name'];
        $subject = $_POST['subject'];
        $qualification = $_POST['qualification'];
        $email = $_POST['email'];
        $phone = $_POST['phone'];
        $is_hod = isset($_POST['is_hod']) ? 1 : 0;
        $is_counsellor = isset($_POST['is_counsellor']) ? 1 : 0;
        $profile_image = 'default.jpg';
        if (isset($_FILES['profile_image']) && $_FILES['profile_image']['error'] === UPLOAD_ERR_OK) {
            $upload_dir = 'assets/images/faculty/';
            $file_extension = pathinfo($_FILES['profile_image']['name'], PATHINFO_EXTENSION);
            $profile_image = uniqid() . '.' . $file_extension;
            move_uploaded_file($_FILES['profile_image']['tmp_name'], $upload_dir . $profile_image);
        }
        $stmt = $pdo->prepare("INSERT INTO faculty (full_name, subject, qualification, email, phone, profile_image, is_hod, is_counsellor) VALUES (?, ?, ?, ?, ?, ?, ?, ?)");
        $stmt->execute([$full_name, $subject, $qualification, $email, $phone, $profile_image, $is_hod, $is_counsellor]);
        $success_message = "Faculty added successfully.";
    }

    // Update Faculty
    if (isset($_POST['update_faculty'])) {
        $faculty_id = $_POST['faculty_id'];
        $full_name = $_POST['full_name'];
        $subject = $_POST['subject'];
        $qualification = $_POST['qualification'];
        $email = $_POST['email'];
        $phone = $_POST['phone'];
        $is_hod = isset($_POST['is_hod']) ? 1 : 0;
        $is_counsellor = isset($_POST['is_counsellor']) ? 1 : 0;
        $existing_profile_image = $_POST['existing_profile_image'];
        $profile_image = $existing_profile_image;

        if (isset($_FILES['profile_image']) && $_FILES['profile_image']['error'] === UPLOAD_ERR_OK) {
            $upload_dir = 'assets/images/faculty/';
            $file_extension = pathinfo($_FILES['profile_image']['name'], PATHINFO_EXTENSION);
            $profile_image = uniqid() . '.' . $file_extension;
            move_uploaded_file($_FILES['profile_image']['tmp_name'], $upload_dir . $profile_image);
        }

        $stmt = $pdo->prepare("UPDATE faculty SET full_name=?, subject=?, qualification=?, email=?, phone=?, profile_image=?, is_hod=?, is_counsellor=? WHERE id=?");
        $stmt->execute([$full_name, $subject, $qualification, $email, $phone, $profile_image, $is_hod, $is_counsellor, $faculty_id]);
        $success_message = "Faculty updated successfully.";
        header("Location: admin_dashboard.php#manage-faculty");
        exit();
    }

    // Add Student
    if (isset($_POST['add_student'])) {
        $roll_number = $_POST['roll_number'];
        $full_name = $_POST['full_name'];
        $date_of_birth = $_POST['date_of_birth'];
        $email = $_POST['email'];
        $phone = $_POST['phone'];
        $address = $_POST['address'];
        $year = $_POST['year'];
        $semester = $_POST['semester'];
        $is_admin_profile = isset($_POST['is_admin_profile']) ? 1 : 0;
        $hashed_password = password_hash($date_of_birth, PASSWORD_DEFAULT);
        $stmt = $pdo->prepare("INSERT INTO users (username, password, role) VALUES (?, ?, 'student')");
        $stmt->execute([$roll_number, $hashed_password]);
        $user_id = $pdo->lastInsertId();
        $profile_image = 'default.jpg';
        $is_cr = isset($_POST['is_cr']) ? 1 : 0;
        $is_lr = isset($_POST['is_lr']) ? 1 : 0;
        $is_acr = isset($_POST['is_acr']) ? 1 : 0;
        if (isset($_FILES['profile_image']) && $_FILES['profile_image']['error'] === UPLOAD_ERR_OK) {
            $upload_dir = 'assets/images/students/';
            $file_extension = pathinfo($_FILES['profile_image']['name'], PATHINFO_EXTENSION);
            $profile_image = uniqid() . '.' . $file_extension;
            move_uploaded_file($_FILES['profile_image']['tmp_name'], $upload_dir . $profile_image);
        }
        $stmt = $pdo->prepare("INSERT INTO students (user_id, roll_number, full_name, date_of_birth, email, phone, address, profile_image, year, semester, is_admin_profile, is_cr, is_lr, is_acr) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");
        $stmt->execute([$user_id, $roll_number, $full_name, $date_of_birth, $email, $phone, $address, $profile_image, $year, $semester, $is_admin_profile, $is_cr, $is_lr, $is_acr]);
        $success_message = "Student added successfully.";
    }

    // Update Student
    if (isset($_POST['update_student'])) {
        $student_id = $_POST['student_id'];
        $roll_number = $_POST['roll_number'];
        $full_name = $_POST['full_name'];
        $date_of_birth = $_POST['date_of_birth'];
        $email = $_POST['email'];
        $phone = $_POST['phone'];
        $address = $_POST['address'];
        $year = $_POST['year'];
        $semester = $_POST['semester'];
        $is_admin_profile = isset($_POST['is_admin_profile']) ? 1 : 0;
        $existing_profile_image = $_POST['existing_profile_image'];
        $profile_image = $existing_profile_image;
        $is_cr = isset($_POST['is_cr']) ? 1 : 0;
        $is_lr = isset($_POST['is_lr']) ? 1 : 0;
        $is_acr = isset($_POST['is_acr']) ? 1 : 0;
        if (isset($_FILES['profile_image']) && $_FILES['profile_image']['error'] === UPLOAD_ERR_OK) {
            $upload_dir = 'assets/images/students/';
            $file_extension = pathinfo($_FILES['profile_image']['name'], PATHINFO_EXTENSION);
            $profile_image = uniqid() . '.' . $file_extension;
            move_uploaded_file($_FILES['profile_image']['tmp_name'], $upload_dir . $profile_image);
        }
        $stmt = $pdo->prepare("UPDATE students SET roll_number=?, full_name=?, date_of_birth=?, email=?, phone=?, address=?, profile_image=?, year=?, semester=?, is_admin_profile=?, is_cr=?, is_lr=?, is_acr=? WHERE id=?");
        $stmt->execute([$roll_number, $full_name, $date_of_birth, $email, $phone, $address, $profile_image, $year, $semester, $is_admin_profile, $is_cr, $is_lr, $is_acr, $student_id]);
        $stmt = $pdo->prepare("SELECT user_id FROM students WHERE id = ?");
        $stmt->execute([$student_id]);
        $row = $stmt->fetch(PDO::FETCH_ASSOC);
        if ($row) {
            $user_id = $row['user_id'];
            $stmt = $pdo->prepare("UPDATE users SET username=? WHERE id=?");
            $stmt->execute([$roll_number, $user_id]);
        }
        $success_message = "Student updated successfully.";
        header("Location: admin_dashboard.php#manage-students");
        exit();
    }

    // Add Attendance
    if (isset($_POST['add_attendance'])) {
        $student_id = $_POST['student_id'];
        $date = $_POST['date'];
        $attendance_data = [];
        for ($i = 1; $i <= 8; $i++) {
            $attendance_data["period$i"] = isset($_POST["period$i"]) ? 1 : 0;
        }
        $stmt = $pdo->prepare("SELECT id FROM students WHERE id = ?");
        $stmt->execute([$student_id]);
        if ($stmt->fetchColumn()) {
            $stmt = $pdo->prepare("SELECT id FROM attendance WHERE student_id = ? AND date = ?");
            $stmt->execute([$student_id, $date]);
            $existing_attendance = $stmt->fetch(PDO::FETCH_ASSOC);
            if ($existing_attendance) {
                $stmt = $pdo->prepare("UPDATE attendance SET period1=?, period2=?, period3=?, period4=?, period5=?, period6=?, period7=?, period8=? WHERE id=?");
                $stmt->execute([
                    $attendance_data['period1'],
                    $attendance_data['period2'],
                    $attendance_data['period3'],
                    $attendance_data['period4'],
                    $attendance_data['period5'],
                    $attendance_data['period6'],
                    $attendance_data['period7'],
                    $attendance_data['period8'],
                    $existing_attendance['id']
                ]);
                $success_message = "Attendance updated successfully.";
            } else {
                $stmt = $pdo->prepare("INSERT INTO attendance (student_id, date, period1, period2, period3, period4, period5, period6, period7, period8) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");
                $stmt->execute([
                    $student_id,
                    $date,
                    $attendance_data['period1'],
                    $attendance_data['period2'],
                    $attendance_data['period3'],
                    $attendance_data['period4'],
                    $attendance_data['period5'],
                    $attendance_data['period6'],
                    $attendance_data['period7'],
                    $attendance_data['period8']
                ]);
                $success_message = "Attendance added successfully.";
            }
        } else {
            $error_message = "Invalid student selected for attendance.";
        }
    }

    // Bulk Attendance Upload
    if (isset($_POST['bulk_attendance'])) {
        $date = $_POST['bulk_date'];
        $year = $_POST['bulk_year'];
        $semester = $_POST['bulk_semester'];
        $stmt = $pdo->prepare("SELECT id FROM students WHERE year = ? AND semester = ?");
        $stmt->execute([$year, $semester]);
        $students = $stmt->fetchAll(PDO::FETCH_ASSOC);
        $success_count = 0;
        $error_count = 0;
        foreach ($students as $student) {
            $student_id = $student['id'];
            $stmt = $pdo->prepare("SELECT id FROM attendance WHERE student_id = ? AND date = ?");
            $stmt->execute([$student_id, $date]);
            $existing = $stmt->fetch(PDO::FETCH_ASSOC);
            if (!$existing) {
                $stmt = $pdo->prepare("INSERT INTO attendance (student_id, date, period1, period2, period3, period4, period5, period6, period7, period8) VALUES (?, ?, 0, 0, 0, 0, 0, 0, 0, 0)");
                if ($stmt->execute([$student_id, $date])) {
                    $success_count++;
                } else {
                    $error_count++;
                }
            }
        }
        $success_message = "Bulk attendance created. $success_count records added, $error_count errors.";
    }
}

// Add Timetable
if (isset($_POST['upload_timetable_image'])) {
    if (isset($_FILES['timetable_image']) && $_FILES['timetable_image']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/timetable/';
        if (!is_dir($upload_dir)) {
            mkdir($upload_dir, 0755, true);
        }

        $allowed_ext = ['jpg', 'jpeg', 'png', 'gif', 'webp'];
        $originalName = $_FILES['timetable_image']['name'];
        $ext = strtolower(pathinfo($originalName, PATHINFO_EXTENSION));

        if (!in_array($ext, $allowed_ext)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed_ext);
        } else {
            // Remove any previous timetable_current.* files
            foreach (glob($upload_dir . 'timetable_current.*') as $old) {
                @unlink($old);
            }

            $target = $upload_dir . 'timetable_current.' . $ext;

            if (move_uploaded_file($_FILES['timetable_image']['tmp_name'], $target)) {
                // Optional: set secure permissions
                @chmod($target, 0644);
                $_SESSION['success_message'] = "Timetable image uploaded successfully.";
                header("Location: admin_dashboard.php#manage-timetable");
                exit();
            } else {
                $error_message = "Failed to move uploaded file.";
            }
        }
    } else {
        $error_message = "No file uploaded or upload error.";
    }
}


// Add Syllabus
if (isset($_POST['add_syllabus'])) {
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $syllabus_content = $_POST['syllabus_content'];
    $file_path = '';
    if (isset($_FILES['syllabus_file']) && $_FILES['syllabus_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/syllabus/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['syllabus_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt', 'zip', 'rar', '7z'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('syll_') . '.' . $ext;
            move_uploaded_file($_FILES['syllabus_file']['tmp_name'], $upload_dir . $safe_name);
            $file_path = $upload_dir . $safe_name;
        }
    }
    $stmt = $pdo->prepare("INSERT INTO syllabus (year, semester, subject, syllabus_content, file_path) VALUES (?, ?, ?, ?, ?)");
    $stmt->execute([$year, $semester, $subject, $syllabus_content, $file_path]);
    $success_message = "Syllabus added successfully.";
}

// Update Syllabus
if (isset($_POST['update_syllabus'])) {
    $syllabus_id = $_POST['syllabus_id'];
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $syllabus_content = $_POST['syllabus_content'];
    $existing_file_path = $_POST['existing_file_path'];
    $file_path = $existing_file_path;

    if (isset($_FILES['syllabus_file']) && $_FILES['syllabus_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/syllabus/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['syllabus_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt', 'zip', 'rar', '7z'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('syll_') . '.' . $ext;
            move_uploaded_file($_FILES['syllabus_file']['tmp_name'], $upload_dir . $safe_name);
            $file_path = $upload_dir . $safe_name;
        }
    }

    $stmt = $pdo->prepare("UPDATE syllabus SET year=?, semester=?, subject=?, syllabus_content=?, file_path=? WHERE id=?");
    $stmt->execute([$year, $semester, $subject, $syllabus_content, $file_path, $syllabus_id]);
    $success_message = "Syllabus updated successfully.";
    header("Location: admin_dashboard.php#manage-syllabus");
    exit();
}

// Add Study Material
if (isset($_POST['add_material'])) {
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $file_path = '';
    if (isset($_FILES['material_file']) && $_FILES['material_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/materials/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['material_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt', 'zip', 'rar', '7z'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('mat_') . '.' . $ext;
            move_uploaded_file($_FILES['material_file']['tmp_name'], $upload_dir . $safe_name);
            $file_path = $upload_dir . $safe_name;
        }
    }
    $stmt = $pdo->prepare("INSERT INTO study_materials (year, semester, subject, file_path) VALUES (?, ?, ?, ?)");
    $stmt->execute([$year, $semester, $subject, $file_path]);
    $success_message = "Question Bank added successfully.";
}


// Update Study Material
if (isset($_POST['update_material'])) {
    $material_id = $_POST['material_id'];
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $existing_file_path = $_POST['existing_file_path'];
    $file_path = $existing_file_path;

    if (isset($_FILES['material_file']) && $_FILES['material_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/materials/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['material_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt', 'zip', 'rar', '7z'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('mat_') . '.' . $ext;
            move_uploaded_file($_FILES['material_file']['tmp_name'], $upload_dir . $safe_name);
            $file_path = $upload_dir . $safe_name;
        }
    }

    $stmt = $pdo->prepare("UPDATE study_materials SET year=?, semester=?, subject=?, file_path=? WHERE id=?");
    $stmt->execute([$year, $semester, $subject, $file_path, $material_id]);
    $success_message = "Question Bank updated successfully.";
    header("Location: admin_dashboard.php#manage-materials");
    exit();
}

// Add Bit Bank
if (isset($_POST['add_bit_bank'])) {
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $file_path = '';
    if (isset($_FILES['bit_bank_file']) && $_FILES['bit_bank_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/bit_bank/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['bit_bank_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('bit_') . '.' . $ext;
            move_uploaded_file($_FILES['bit_bank_file']['tmp_name'], $upload_dir . $safe_name);
            $file_path = $upload_dir . $safe_name;
        }
    }
    $stmt = $pdo->prepare("INSERT INTO bit_bank (year, semester, subject, file_path) VALUES (?, ?, ?, ?)");
    $stmt->execute([$year, $semester, $subject, $file_path]);
    $success_message = "Bit Bank added successfully.";
}

// Update Bit Bank
if (isset($_POST['update_bit_bank'])) {
    $bit_bank_id = $_POST['bit_bank_id'];
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $existing_file_path = $_POST['existing_file_path'];
    $file_path = $existing_file_path;

    if (isset($_FILES['bit_bank_file']) && $_FILES['bit_bank_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/bit_bank/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['bit_bank_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('bit_') . '.' . $ext;
            move_uploaded_file($_FILES['bit_bank_file']['tmp_name'], $upload_dir . $safe_name);
            $file_path = $upload_dir . $safe_name;
        }
    }

    $stmt = $pdo->prepare("UPDATE bit_bank SET year=?, semester=?, subject=?, file_path=? WHERE id=?");
    $stmt->execute([$year, $semester, $subject, $file_path, $bit_bank_id]);
    $success_message = "Bit Bank updated successfully.";
    header("Location: admin_dashboard.php#manage-bit-bank");
    exit();
}

// Add Question Bank
if (isset($_POST['add_question_bank'])) {
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $question_file = '';
    if (isset($_FILES['question_file']) && $_FILES['question_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/question_bank/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['question_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('qbank_') . '.' . $ext;
            move_uploaded_file($_FILES['question_file']['tmp_name'], $upload_dir . $safe_name);
            $question_file = $upload_dir . $safe_name;
        }
    }
    $stmt = $pdo->prepare("INSERT INTO question_bank (year, semester, subject, question_file) VALUES (?, ?, ?, ?)");
    $stmt->execute([$year, $semester, $subject, $question_file]);
    $success_message = "Question Bank added successfully.";
}

// Update Question Bank
if (isset($_POST['update_question_bank'])) {
    $question_bank_id = $_POST['question_bank_id'];
    $year = $_POST['year'];
    $semester = $_POST['semester'];
    $subject = $_POST['subject'];
    $existing_question_file = $_POST['existing_question_file'];
    $question_file = $existing_question_file;

    if (isset($_FILES['question_file']) && $_FILES['question_file']['error'] === UPLOAD_ERR_OK) {
        $upload_dir = 'assets/uploads/question_bank/';
        if (!is_dir($upload_dir)) mkdir($upload_dir, 0777, true);
        $file_name = $_FILES['question_file']['name'];
        $ext = strtolower(pathinfo($file_name, PATHINFO_EXTENSION));
        $allowed = ['pdf', 'doc', 'docx', 'docm', 'odt'];
        if (!in_array($ext, $allowed)) {
            $error_message = "Invalid file type. Allowed: " . implode(', ', $allowed);
        } else {
            $safe_name = uniqid('qbank_') . '.' . $ext;
            move_uploaded_file($_FILES['question_file']['tmp_name'], $upload_dir . $safe_name);
            $question_file = $upload_dir . $safe_name;
        }
    }

    $stmt = $pdo->prepare("UPDATE question_bank SET year=?, semester=?, subject=?, question_file=? WHERE id=?");
    $stmt->execute([$year, $semester, $subject, $question_file, $question_bank_id]);
    $success_message = "Question Bank updated successfully.";
    header("Location: admin_dashboard.php#manage-question-bank");
    exit();
}

// Handle delete actions
if (isset($_GET['delete'])) {
    if ($_GET['type'] === 'announcement' && isset($_GET['id'])) {
        $stmt = $pdo->prepare("DELETE FROM announcements WHERE id = ?");
        $stmt->execute([$_GET['id']]);
        echo '<script>alert("Announcement deleted successfully");</script>';
        header("Location: admin_dashboard.php#manage-announcements");
        exit();
    }
    $type = $_GET['type'];
    $id = $_GET['id'];

    // Special case for achievement to handle file deletion
    $type = $_GET['type'];
    $id = $_GET['id'] ?? null;
    if ($type === 'achievement' && $id) {
        // remove DB record and unlink file if exists
        $stmt = $pdo->prepare("SELECT file_path FROM achievements WHERE id = ?");
        $stmt->execute([$id]);
        $row = $stmt->fetch(PDO::FETCH_ASSOC);
        if ($row) {
            if (!empty($row['file_path']) && file_exists($row['file_path'])) {
                @unlink($row['file_path']);
            }
            $stmt = $pdo->prepare("DELETE FROM achievements WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Achievement image deleted successfully");</script>';
        }
        header("Location: admin_dashboard.php#manage-achievements");
        exit();
    }

    switch ($type) {
        case 'contact_message':
            $stmt = $pdo->prepare("DELETE FROM contact_messages WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Contact message deleted successfully");</script>';
            header("Location: admin_dashboard.php#contact-messages");
            exit();
        case 'faculty':
            $stmt = $pdo->prepare("DELETE FROM faculty WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Faculty deleted successfully");</script>';
            break;

        case 'student':
            // First get user_id to delete from users table
            $stmt = $pdo->prepare("SELECT user_id FROM students WHERE id = ?");
            $stmt->execute([$id]);
            $student = $stmt->fetch(PDO::FETCH_ASSOC);

            if ($student) {
                $stmt = $pdo->prepare("DELETE FROM students WHERE id = ?");
                $stmt->execute([$id]);

                $stmt = $pdo->prepare("DELETE FROM users WHERE id = ?");
                $stmt->execute([$student['user_id']]);

                echo '<script>alert("Student deleted successfully");</script>';
            }
            break;

        case 'syllabus':
            $stmt = $pdo->prepare("DELETE FROM syllabus WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Syllabus deleted successfully");</script>';
            break;

        case 'timetable':
            $stmt = $pdo->prepare("DELETE FROM timetable WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Timetable deleted successfully");</script>';
            break;

        case 'material':
            $stmt = $pdo->prepare("DELETE FROM study_materials WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Study material deleted successfully");</script>';
            break;

        case 'attendance':
            $stmt = $pdo->prepare("DELETE FROM attendance WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Attendance record deleted successfully");</script>';
            break;

        case 'bit_bank':
            $stmt = $pdo->prepare("DELETE FROM bit_bank WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Bit Bank deleted successfully");</script>';
            break;

        case 'question_bank':
            $stmt = $pdo->prepare("DELETE FROM question_bank WHERE id = ?");
            $stmt->execute([$id]);
            echo '<script>alert("Question Bank deleted successfully");</script>';
            break;
    }
    header("Location: admin_dashboard.php");
    exit();
}

// =============================================
// CORRECTED AJAX HANDLERS SECTION
// =============================================

// Handle AJAX requests
if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['ajax_action'])) {
    // Clear any previous output
    if (ob_get_length())
        ob_clean();

    header('Content-Type: application/json');

    $action = $_POST['ajax_action'];
    $response = ['status' => 'error', 'message' => 'Unknown action'];

    try {
        switch ($action) {
            // 🔹 CHECK ROLL NUMBER EXISTS IN DATABASE - CORRECTED
            case 'check_roll_number':
                $roll_number = trim($_POST['user_roll_number'] ?? '');

                if (empty($roll_number)) {
                    $response = ['status' => 'error', 'message' => 'Roll number is required', 'exists' => false];
                    break;
                }

                // DIRECT QUERY - Check if roll number exists in students table
                $stmt = $pdo->prepare("
                    SELECT s.id, s.roll_number, s.full_name, s.email, u.id as user_id
                    FROM students s 
                    LEFT JOIN users u ON s.user_id = u.id 
                    WHERE s.roll_number = ?
                ");
                $stmt->execute([$roll_number]);
                $student = $stmt->fetch(PDO::FETCH_ASSOC);

                if ($student && !empty($student['id'])) {
                    $response = [
                        'status' => 'success',
                        'exists' => true,
                        'message' => 'Roll number found',
                        'user_data' => [
                            'full_name' => $student['full_name'] ?? 'Name not set',
                            'email' => $student['email'] ?? 'Email not set',
                            'user_id' => $student['user_id']
                        ]
                    ];
                } else {
                    $response = [
                        'status' => 'success',
                        'exists' => false,
                        'message' => 'Roll number not found in system'
                    ];
                }
                break;

            // 🔹 SEND OTP TO USER'S EMAIL - CORRECTED
            case 'send_otp':
                $roll_number = trim($_POST['user_roll_number'] ?? '');

                if (empty($roll_number)) {
                    $response = ['status' => 'error', 'message' => 'Roll number is required'];
                    break;
                }

                // Get student details directly from students table
                $stmt = $pdo->prepare("
                    SELECT s.id, s.email, s.full_name, u.id as user_id 
                    FROM students s 
                    LEFT JOIN users u ON s.user_id = u.id 
                    WHERE s.roll_number = ?
                ");
                $stmt->execute([$roll_number]);
                $student = $stmt->fetch(PDO::FETCH_ASSOC);

                if (!$student) {
                    $response = ['status' => 'error', 'message' => 'Invalid roll number - student not found'];
                    break;
                }

                if (empty($student['email'])) {
                    $response = ['status' => 'error', 'message' => 'No email found for this student'];
                    break;
                }

                // Generate OTP
                $otp = rand(100000, 999999);

                // Store OTP in session with expiration
                $_SESSION['password_change_otp'] = [
                    'user_id' => $student['user_id'],
                    'roll_number' => $roll_number,
                    'otp' => $otp,
                    'expires' => time() + 600, // 10 minutes
                    'user_email' => $student['email'],
                    'user_name' => $student['full_name']
                ];

                // Send OTP via email
                $mail_sent = sendOtpEmail($student['email'], $student['full_name'], $otp);

                if ($mail_sent) {
                    $response = [
                        'status' => 'success',
                        'message' => 'OTP sent successfully to your registered email',
                        'otp_expires' => 10 // minutes
                    ];
                } else {
                    // Clear OTP if email failed
                    unset($_SESSION['password_change_otp']);
                    $response = ['status' => 'error', 'message' => 'Failed to send OTP email. Please try again.'];
                }
                break;

            // 🔹 CHANGE USER PASSWORD - CORRECTED
            case 'change_password':
                $roll_number = trim($_POST['user_roll_number'] ?? '');
                $new_password = $_POST['new_password'] ?? '';
                $confirm_password = $_POST['confirm_password'] ?? '';
                $otp = $_POST['otp'] ?? '';

                // Validation checks
                if (empty($roll_number) || empty($new_password) || empty($confirm_password) || empty($otp)) {
                    $response = ['status' => 'error', 'message' => 'All fields are required'];
                    break;
                }

                if ($new_password !== $confirm_password) {
                    $response = ['status' => 'error', 'message' => 'Passwords do not match'];
                    break;
                }

                if (strlen($new_password) < 6) {
                    $response = ['status' => 'error', 'message' => 'Password must be at least 6 characters'];
                    break;
                }

                // Verify OTP session exists and is valid
                if (!isset($_SESSION['password_change_otp']) || !is_array($_SESSION['password_change_otp'])) {
                    $response = ['status' => 'error', 'message' => 'OTP session expired. Please request a new OTP.'];
                    break;
                }

                $otp_data = $_SESSION['password_change_otp'];

                // Verify OTP matches and hasn't expired
                if ($otp_data['roll_number'] !== $roll_number) {
                    $response = ['status' => 'error', 'message' => 'Roll number mismatch with OTP session'];
                    break;
                }

                if ($otp_data['otp'] != $otp) { // Loose comparison for string vs int
                    $response = ['status' => 'error', 'message' => 'Invalid OTP'];
                    break;
                }

                if ($otp_data['expires'] < time()) {
                    $response = ['status' => 'error', 'message' => 'OTP has expired. Please request a new one.'];
                    break;
                }

                // Get user data from session
                $user_id = $otp_data['user_id'];
                $user_email = $otp_data['user_email'];
                $user_name = $otp_data['user_name'];

                // Hash new password
                $hashed_password = password_hash($new_password, PASSWORD_DEFAULT);

                // Update password in database
                $stmt = $pdo->prepare("UPDATE users SET password = ? WHERE id = ?");
                $update_result = $stmt->execute([$hashed_password, $user_id]);

                if ($update_result && $stmt->rowCount() > 0) {
                    // Send confirmation email
                    sendPasswordChangeConfirmationEmail($user_email, $user_name);

                    // 🔥 FIX: Clear OTP session AND reset cooldown
                    unset($_SESSION['password_change_otp']);

                    $response = [
                        'status' => 'success',
                        'message' => 'Password changed successfully!',
                        'reset_cooldown' => true // Signal to reset cooldown in JavaScript
                    ];
                } else {
                    $response = ['status' => 'error', 'message' => 'Failed to update password in database'];
                }
                break;

            // 🔹 CHECK PASSWORD STRENGTH (Optional enhancement)
            case 'check_password_strength':
                $password = $_POST['password'] ?? '';

                if (empty($password)) {
                    $response = ['status' => 'error', 'message' => 'Password is empty'];
                    break;
                }

                $strength = calculatePasswordStrength($password);
                $response = [
                    'status' => 'success',
                    'strength' => $strength['level'],
                    'score' => $strength['score'],
                    'message' => $strength['message']
                ];
                break;

            default:
                $response = ['status' => 'error', 'message' => 'Invalid action'];
                break;
        }
    } catch (PDOException $e) {
        error_log("Database error in AJAX handler {$action}: " . $e->getMessage());
        $response = ['status' => 'error', 'message' => 'Database error occurred'];
    } catch (Exception $e) {
        error_log("General error in AJAX handler {$action}: " . $e->getMessage());
        $response = ['status' => 'error', 'message' => 'An unexpected error occurred'];
    }

    echo json_encode($response);
    exit;
}

// =============================================
// SUPPORTING FUNCTIONS (Keep your existing ones)
// =============================================

/**
 * Send OTP email to user
 */
function sendOtpEmail($email, $name, $otp)
{
    try {
        require_once 'includes/PHPMailer/PHPMailer.php';
        require_once 'includes/PHPMailer/SMTP.php';
        require_once 'includes/PHPMailer/Exception.php';

        $mail = new \PHPMailer\PHPMailer\PHPMailer(true);

        $mail->isSMTP();
        $mail->Host = env('SMTP_HOST', 'smtp.gmail.com');
        $mail->SMTPAuth = true;
        $mail->Username = env('SMTP_USERNAME', '');
        $mail->Password = env('SMTP_PASSWORD', '');
        $mail->SMTPSecure = \PHPMailer\PHPMailer\PHPMailer::ENCRYPTION_STARTTLS;
        $mail->Port = (int) env('SMTP_PORT', 587);

        $mail->setFrom(env('SMTP_FROM', env('SMTP_USERNAME', '')), env('SMTP_FROM_NAME', 'CAI Admin'));
        $mail->addAddress($email, $name);
        $mail->Subject = 'Password Change OTP - CAI System';

        $mail->Body = "
Dear {$name},

You have requested to change your password. Please use the following OTP to proceed:

🔐 OTP: {$otp}

This OTP is valid for 10 minutes only.

If you did not request this password change, please contact the administration immediately.

Best regards,
CAI Admin System
        ";

        $mail->isHTML(false);
        return $mail->send();
    } catch (Exception $e) {
        error_log("Email sending failed: " . $e->getMessage());
        return false;
    }
}

/**
 * Send password change confirmation email
 */
function sendPasswordChangeConfirmationEmail($email, $name)
{
    try {
        require_once 'includes/PHPMailer/PHPMailer.php';
        require_once 'includes/PHPMailer/SMTP.php';
        require_once 'includes/PHPMailer/Exception.php';

        $mail = new \PHPMailer\PHPMailer\PHPMailer(true);

        $mail->isSMTP();
        $mail->Host = env('SMTP_HOST', 'smtp.gmail.com');
        $mail->SMTPAuth = true;
        $mail->Username = env('SMTP_USERNAME', '');
        $mail->Password = env('SMTP_PASSWORD', '');
        $mail->SMTPSecure = \PHPMailer\PHPMailer\PHPMailer::ENCRYPTION_STARTTLS;
        $mail->Port = (int) env('SMTP_PORT', 587);

        $mail->setFrom(env('SMTP_FROM', env('SMTP_USERNAME', '')), env('SMTP_FROM_NAME', 'CAI Admin'));
        $mail->addAddress($email, $name);
        $mail->Subject = 'Password Changed Successfully - CAI System';

        $mail->Body = "
Dear {$name},

Your password has been changed successfully.

If you did not make this change, please contact the administration immediately.

Best regards,
CAI Admin System
        ";

        $mail->isHTML(false);
        return $mail->send();
    } catch (Exception $e) {
        error_log("Confirmation email sending failed: " . $e->getMessage());
        return false;
    }
}

/**
 * Calculate password strength
 */
function calculatePasswordStrength($password)
{
    $score = 0;
    $messages = [];

    // Length check
    if (strlen($password) >= 8) {
        $score++;
    } else {
        $messages[] = 'At least 8 characters';
    }

    // Uppercase check
    if (preg_match('/[A-Z]/', $password)) {
        $score++;
    } else {
        $messages[] = 'Uppercase letters';
    }

    // Lowercase check
    if (preg_match('/[a-z]/', $password)) {
        $score++;
    } else {
        $messages[] = 'Lowercase letters';
    }

    // Numbers check
    if (preg_match('/[0-9]/', $password)) {
        $score++;
    } else {
        $messages[] = 'Numbers';
    }

    // Special characters check
    if (preg_match('/[^A-Za-z0-9]/', $password)) {
        $score++;
    } else {
        $messages[] = 'Special characters';
    }

    // Determine strength level
    $levels = [
        1 => ['level' => 'Very Weak', 'color' => '#dc3545'],
        2 => ['level' => 'Weak', 'color' => '#ffc107'],
        3 => ['level' => 'Fair', 'color' => '#fd7e14'],
        4 => ['level' => 'Good', 'color' => '#20c997'],
        5 => ['level' => 'Strong', 'color' => '#198754']
    ];

    $level = $levels[max(1, min($score, 5))];

    return [
        'score' => $score,
        'level' => $level['level'],
        'color' => $level['color'],
        'message' => $messages ? 'Consider adding: ' . implode(', ', $messages) : 'Strong password!'
    ];
}
?>

<style>
    /* Show only ~5 rows; rest scrollable with header sticky */
    .existing-table-wrapper {
        max-height: calc((5 * 56px) + 56px);
        /* 5 rows (approx 56px each) + header height */
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
        border-radius: 8px;
        background: #fff;
        padding: 0.25rem;
        box-shadow: 0 1px 0 rgba(0, 0, 0, 0.02);
    }

    /* Ensure table takes full width */
    .existing-table-wrapper table {
        width: 100%;
        border-collapse: collapse;
    }

    /* Keep the header visible while scrolling */
    .existing-table-wrapper thead th {
        position: sticky;
        top: 0;
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        z-index: 3;
        padding: 0.6rem 0.9rem;
        text-align: left;
        border-bottom: 1px solid #e6e6e6;
    }

    /* Row styling */
    .existing-table-wrapper tbody td {
        padding: 0.7rem 0.9rem;
        border-bottom: 1px solid #f0f0f0;
    }

    /* Responsive tweak for small screens */
    @media (max-width: 600px) {
        .existing-table-wrapper {
            max-height: 320px;
        }

        .existing-table-wrapper thead th,
        .existing-table-wrapper tbody td {
            padding: 0.45rem 0.6rem;
            font-size: 0.92rem;
        }
    }
</style>

<div class="main-content">
    <?php include 'includes/sidebar.php'; ?>
    <div class="content-sections">
        <section class="content-section">
            <h2>Admin Dashboard</h2>
            <?php if (isset($success_message)): ?>
                <div class="alert alert-success"
                    style="background:#e3fbe3; color:#155724; padding:1rem; border-radius:8px; margin-bottom:1rem;">
                    <?php echo htmlspecialchars($success_message); ?>
                </div>
            <?php endif; ?>
            <?php if (isset($error_message)): ?>
                <div class="alert alert-danger"
                    style="background:#ffe3e3; color:#a00; padding:1rem; border-radius:8px; margin-bottom:1rem;">
                    <?php echo htmlspecialchars($error_message); ?>
                </div>
            <?php endif; ?>


            <div style="display: flex; gap: 1rem; flex-wrap: wrap; margin-bottom: 2rem;">
                <a href="#manage-announcements" class="btn">Manage Announcements</a>
                <a href="#manage-achievements" class="btn">Manage Achievements</a>
                <a href="#manage-faculty" class="btn">Manage Faculty</a>
                <a href="#manage-hod" class="btn">Manage HOD</a>
                <a href="#manage-counsellor" class="btn">Manage Counsellor</a>
                <a href="#manage-students" class="btn">Manage Students</a>
                <a href="#manage-attendance" class="btn">Manage Attendance</a>
                <a href="#manage-syllabus" class="btn">Manage Syllabus</a>
                <a href="#manage-timetable" class="btn">Manage Timetable</a>
                <a href="#manage-materials" class="btn">Manage Question Bank</a>
                <a href="#manage-bit-bank" class="btn">Manage Bit Bank</a>
                <a href="#manage-question-bank" class="btn">Manage Question Bank with answers</a>
                <a href="#contact-messages" class="btn">Contact Messages</a>
                <a href="#change-password" class="btn">Change Password</a>
            </div>

            <!-- Contact Messages Section -->
            <div id="contact-messages" class="content-subsection" style="margin-bottom:2rem;">
                <h3>Contact Messages</h3>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Name</th>
                                <th>Email</th>
                                <th>Subject</th>
                                <th>Message</th>
                                <th>Date</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM contact_messages ORDER BY created_at DESC");
                            $messages = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            foreach ($messages as $msg) {
                                echo '<tr>';
                                echo '<td>' . $msg['id'] . '</td>';
                                echo '<td>' . htmlspecialchars($msg['name']) . '</td>';
                                echo '<td>' . htmlspecialchars($msg['email']) . '</td>';
                                echo '<td>' . htmlspecialchars($msg['subject']) . '</td>';
                                echo '<td>' . nl2br(htmlspecialchars($msg['message'])) . '</td>';
                                echo '<td>' . $msg['created_at'] . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?delete=true&type=contact_message&id=' . $msg['id'] . '#contact-messages" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this message?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
            </div>

            <!-- Manage Announcements Section -->
            <div id="manage-announcements" class="content-subsection">
                <h3>Manage Announcements</h3>
                <form method="POST" style="margin-bottom:2rem;">
                    <div class="form-group">
                        <label class="form-label">Title</label>
                        <input type="text" name="title" class="form-input" required>
                    </div>
                    <div class="form-group">
                        <label class="form-label">Message</label>
                        <textarea name="message" class="form-input" rows="3" required></textarea>
                    </div>
                    <button type="submit" name="add_announcement" class="btn">Add Announcement</button>
                </form>
                <h4>Existing Announcements</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Title</th>
                                <th>Message</th>
                                <th>Date</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM announcements ORDER BY created_at DESC");
                            $announcements = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            foreach ($announcements as $a) {
                                echo '<tr>';
                                echo '<td>' . $a['id'] . '</td>';
                                echo '<td>' . htmlspecialchars($a['title']) . '</td>';
                                echo '<td>' . nl2br(htmlspecialchars($a['message'])) . '</td>';
                                echo '<td>' . $a['created_at'] . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=announcement&id=' . $a['id'] . '#manage-announcements" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=announcement&id=' . $a['id'] . '#manage-announcements" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this announcement?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
                <?php
                // Show edit form if editing announcement
                if (isset($_GET['edit']) && $_GET['type'] === 'announcement' && isset($_GET['id'])) {
                    $edit_id = $_GET['id'];
                    $stmt = $pdo->prepare("SELECT * FROM announcements WHERE id = ?");
                    $stmt->execute([$edit_id]);
                    $edit_announcement = $stmt->fetch(PDO::FETCH_ASSOC);
                    if ($edit_announcement) {
                ?>
                        <form method="POST" style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                            <h4>Edit Announcement (ID: <?php echo $edit_announcement['id']; ?>)</h4>
                            <input type="hidden" name="announcement_id" value="<?php echo $edit_announcement['id']; ?>">

                            <div class="form-group">
                                <label class="form-label">Title</label>
                                <input type="text" name="title" class="form-input"
                                    value="<?php echo htmlspecialchars($edit_announcement['title']); ?>" required>
                            </div>
                            <div class="form-group">
                                <label class="form-label">Message</label>
                                <textarea name="message" class="form-input" rows="3"
                                    required><?php echo htmlspecialchars($edit_announcement['message']); ?></textarea>
                            </div>
                            <button type="submit" name="update_announcement" class="btn">Update Announcement</button>
                            <a href="admin_dashboard.php#manage-announcements" class="btn"
                                style="background:#ccc; color:#333;">Cancel</a>
                        </form>
                <?php
                    }
                }
                ?>
            </div>

            <!-- Manage Achievements Section -->
            <div id="manage-achievements" class="content-subsection">
                <h3>Manage Achievements</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom:1.2rem; max-width:520px;">
                    <div class="form-group">
                        <label class="form-label">Upload Achievement Image</label>
                        <input type="file" name="achievement_image" class="form-input" accept="image/*" required>
                    </div>
                    <div class="form-group">
                        <label class="form-label">Alt / Caption (optional)</label>
                        <input type="text" name="alt_text" class="form-input" placeholder="Short caption">
                    </div>
                    <button type="submit" name="add_achievement" class="btn">Upload Achievement</button>
                </form>

                <h4>Existing Achievement Images</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Preview</th>
                                <th>Alt / Caption</th>
                                <th>Uploaded At</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            // Ensure table existence and fetch rows (safe fallback)
                            $pdo->exec("CREATE TABLE IF NOT EXISTS achievements (
                    id INT AUTO_INCREMENT PRIMARY KEY,
                    file_path VARCHAR(255) NOT NULL,
                    alt_text VARCHAR(255) DEFAULT '',
                    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
                ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;");
                            $stmt = $pdo->query("SELECT * FROM achievements ORDER BY created_at ASC");
                            $achievements = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            foreach ($achievements as $a) {
                                $preview = htmlspecialchars($a['file_path']);
                                echo '<tr>';
                                echo '<td>' . $a['id'] . '</td>';
                                echo '<td><img src="' . $preview . '" alt="' . htmlspecialchars($a['alt_text']) . '" style="width:96px;height:64px;object-fit:cover;border-radius:6px;border:1px solid #eee;"></td>';
                                echo '<td>' . htmlspecialchars($a['alt_text']) . '</td>';
                                echo '<td>' . $a['created_at'] . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?delete=true&type=achievement&id=' . $a['id'] . '#manage-achievements" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Delete this achievement image?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            if (count($achievements) === 0) {
                                echo '<tr><td colspan="5"><em>No achievement images uploaded yet.</em></td></tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
            </div>

            <!-- Insert these sections where you'd like in the admin UI (after Manage Faculty recommended) -->
            <div id="manage-hod" class="content-subsection">
                <h3>Manage HOD</h3>
                <?php
                // fetch faculty list
                $facStmt = $pdo->query("SELECT id, full_name FROM faculty ORDER BY full_name");
                $facList = $facStmt->fetchAll(PDO::FETCH_ASSOC);
                $currentHodId = $pdo->query("SELECT id FROM faculty WHERE is_hod = 1 LIMIT 1")->fetchColumn();
                ?>
                <form method="POST" style="margin-bottom:1rem; max-width:520px;">
                    <div class="form-group">
                        <label class="form-label">Faculty Name</label>
                        <select name="hod_faculty_id" class="form-input" required>
                            <option value="none">-- None --</option>
                            <?php foreach ($facList as $f): ?>
                                <option value="<?php echo $f['id']; ?>" <?php echo ($currentHodId == $f['id']) ? 'selected' : ''; ?>>
                                    <?php echo htmlspecialchars($f['full_name']); ?>
                                </option>
                            <?php endforeach; ?>
                        </select>
                    </div>
                    <button type="submit" name="set_hod" class="btn">Set HOD</button>
                </form>
            </div>

            <div id="manage-counsellor" class="content-subsection">
                <h3>Manage Counsellor</h3>
                <?php
                $currentCounsellorId = $pdo->query("SELECT id FROM faculty WHERE is_counsellor = 1 LIMIT 1")->fetchColumn();
                ?>
                <form method="POST" style="margin-bottom:1rem; max-width:520px;">
                    <div class="form-group">
                        <label class="form-label">Faculty Name</label>
                        <select name="counsellor_faculty_id" class="form-input" required>
                            <option value="none">-- None --</option>
                            <?php foreach ($facList as $f): ?>
                                <option value="<?php echo $f['id']; ?>" <?php echo ($currentCounsellorId == $f['id']) ? 'selected' : ''; ?>>
                                    <?php echo htmlspecialchars($f['full_name']); ?>
                                </option>
                            <?php endforeach; ?>
                        </select>
                    </div>
                    <button type="submit" name="set_counsellor" class="btn">Set Counsellor</button>
                </form>
            </div>

            <!-- Manage Attendance Section -->
            <div id="manage-attendance" class="content-subsection">
                <h3>Manage Attendance (Monthly Summary)</h3>
                <form method="POST" id="attendanceUploadForm" style="margin-bottom:1.5rem;">
                    <label class="form-label">Select Month: </label>
                    <input type="month" name="upload_month" id="attendanceMonth"
                        value="<?php echo isset($_POST['upload_month']) ? htmlspecialchars($_POST['upload_month']) : date('Y-m'); ?>">
                    <button type="button" id="showStudentsBtn" class="btn" style="padding:0.4rem 1.2rem;">Show
                        Students</button>
                    <button type="button" id="closeStudentsBtn" class="btn" style="padding:0.4rem 1.2rem; background:#999; display:none;">Close</button>
                </form>

                <?php
                // --- Attendance Upload Form ---
                if (isset($_POST['show_upload_form']) && isset($_POST['upload_month'])) {
                    $upload_month = $_POST['upload_month'];
                    $stmt = $pdo->query("SELECT id, roll_number, full_name FROM students ORDER BY roll_number");
                    $students = $stmt->fetchAll(PDO::FETCH_ASSOC);
                ?>
                    <form method="POST" id="attendanceSaveForm">
                        <input type="hidden" name="upload_month" value="<?php echo htmlspecialchars($upload_month); ?>">
                        <table class="modern-table" id="attendanceInputTable">
                            <thead>
                                <tr>
                                    <th>Roll No</th>
                                    <th>Name</th>
                                    <th>
                                        No. of Classes Conducted
                                        <br>
                                        <input type="number" id="common_classes_conducted" min="0" style="width:70px;"
                                            placeholder="All" oninput="setAllConducted(this.value)"
                                            value="<?php echo isset($students[0]) ? htmlspecialchars($pdo->query("SELECT classes_conducted FROM attendance_percentage WHERE student_id = {$students[0]['id']} AND month = '{$upload_month}'")->fetchColumn()) : ''; ?>">
                                    </th>
                                    <th>No. of Classes Attended</th>
                                    <th>Percentage</th>
                                </tr>
                            </thead>
                            <tbody>
                                <?php foreach ($students as $index => $stu): ?>
                                    <?php
                                    // Fetch existing attendance for this student and month
                                    $stmtA = $pdo->prepare("SELECT classes_conducted, classes_attended, percentage FROM attendance_percentage WHERE student_id = ? AND month = ?");
                                    $stmtA->execute([$stu['id'], $upload_month]);
                                    $existing = $stmtA->fetch(PDO::FETCH_ASSOC);
                                    $conducted_val = $existing ? $existing['classes_conducted'] : '';
                                    $attended_val = $existing ? $existing['classes_attended'] : '';
                                    $percent_val = $existing ? $existing['percentage'] : '';
                                    ?>
                                    <tr>
                                        <td><?php echo htmlspecialchars($stu['roll_number']); ?></td>
                                        <td><?php echo htmlspecialchars($stu['full_name']); ?></td>
                                        <td>
                                            <input type="number" name="classes_conducted[<?php echo $stu['id']; ?>]" min="0"
                                                style="width:70px;" class="conducted-input" required <?php echo $index === 0 ? 'id="first_conducted"' : ''; ?>
                                                value="<?php echo htmlspecialchars($conducted_val); ?>">
                                        </td>
                                        <td>
                                            <input type="number" name="classes_attended[<?php echo $stu['id']; ?>]" min="0"
                                                style="width:70px;" class="attended-input" required
                                                oninput="autoCalculatePercent(this)"
                                                value="<?php echo htmlspecialchars($attended_val); ?>">
                                        </td>
                                        <td>
                                            <input type="number" name="attendance_percent[<?php echo $stu['id']; ?>]" min="0"
                                                max="100" step="0.01" style="width:70px;" placeholder="%" class="percent-input"
                                                required oninput="manualPercentEdit(this)"
                                                value="<?php echo htmlspecialchars($percent_val); ?>">
                                        </td>
                                    </tr>
                                <?php endforeach; ?>
                            </tbody>
                        </table>
                        <button type="submit" name="save_attendance_percent" class="btn" style="margin-top:1rem;">Save
                            Attendance</button>
                    </form>
                    <script>
                        // Set all "No. of Classes Conducted" fields to the same value
                        function setAllConducted(val) {
                            document.querySelectorAll('.conducted-input').forEach(function(input) {
                                input.value = val;
                                // Trigger recalculation for each row
                                var row = input.closest('tr');
                                var attended = row.querySelector('.attended-input');
                                var percent = row.querySelector('.percent-input');
                                if (attended && percent) {
                                    autoCalculatePercent(attended);
                                }
                            });
                        }

                        // Automatically calculate percentage when attended or conducted changes
                        function autoCalculatePercent(attendedInput) {
                            var row = attendedInput.closest('tr');
                            var conductedInput = row.querySelector('.conducted-input');
                            var percentInput = row.querySelector('.percent-input');
                            var attended = parseFloat(attendedInput.value);
                            var conducted = parseFloat(conductedInput.value);
                            if (!isNaN(attended) && !isNaN(conducted) && conducted > 0) {
                                var percent = ((attended / conducted) * 100).toFixed(2);
                                percentInput.value = percent;
                                percentInput.setAttribute('data-auto', '1');
                            } else {
                                percentInput.value = '';
                            }
                        }

                        // If admin manually edits percentage, mark as manual
                        function manualPercentEdit(percentInput) {
                            percentInput.setAttribute('data-auto', '0');
                        }

                        // When conducted changes, recalculate all percentages
                        document.querySelectorAll('.conducted-input').forEach(function(input) {
                            input.addEventListener('input', function() {
                                var row = input.closest('tr');
                                var attended = row.querySelector('.attended-input');
                                if (attended) autoCalculatePercent(attended);
                            });
                        });

                        // When attended changes, recalculate percentage
                        document.querySelectorAll('.attended-input').forEach(function(input) {
                            input.addEventListener('input', function() {
                                autoCalculatePercent(this);
                            });
                        });
                    </script>
                <?php } ?>

                <?php
                // --- Save Attendance Percentages & Notifications ---
                if (
                    isset($_POST['save_attendance_percent']) &&
                    isset($_POST['attendance_percent']) &&
                    isset($_POST['upload_month']) &&
                    isset($_POST['classes_conducted']) &&
                    isset($_POST['classes_attended'])
                ) {
                    $upload_month = $_POST['upload_month'];
                    foreach ($_POST['attendance_percent'] as $stu_id => $percent) {
                        $classes_conducted = $_POST['classes_conducted'][$stu_id];
                        $classes_attended = $_POST['classes_attended'][$stu_id];

                        // Upsert into attendance_percentage table
                        $stmtCheck = $pdo->prepare("SELECT id FROM students WHERE id = ?");
                        $stmtCheck->execute([$stu_id]);
                        if ($stmtCheck->fetchColumn()) {
                            $stmt = $pdo->prepare("INSERT INTO attendance_percentage (student_id, month, classes_conducted, classes_attended, percentage) VALUES (?, ?, ?, ?, ?) ON DUPLICATE KEY UPDATE classes_conducted=VALUES(classes_conducted), classes_attended=VALUES(classes_attended), percentage=VALUES(percentage)");
                            $stmt->execute([$stu_id, $upload_month, $classes_conducted, $classes_attended, $percent]);

                            // Notification if below 75%
                            if ($percent < 75) {
                                $stmtStu = $pdo->prepare("SELECT full_name, email, phone FROM students WHERE id = ?");
                                $stmtStu->execute([$stu_id]);
                                $stu = $stmtStu->fetch(PDO::FETCH_ASSOC);

                                if ($stu) {
                                    // Calculate overall percentage
                                    $stmtOverall = $pdo->prepare("SELECT SUM(classes_attended) as attended, SUM(classes_conducted) as conducted FROM attendance_percentage WHERE student_id = ?");
                                    $stmtOverall->execute([$stu_id]);
                                    $overall = $stmtOverall->fetch(PDO::FETCH_ASSOC);
                                    $overall_percentage = ($overall && $overall['conducted'] > 0) ? round(($overall['attended'] / $overall['conducted']) * 100, 2) : 'N/A';

                                    $bodyText = "
                            <html>
                            <head>
                                <meta name='viewport' content='width=device-width, initial-scale=1.0'>
                                <style>
                                    @import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');
                                    body { 
                                        font-family: 'Inter', 'Segoe UI', Arial, sans-serif; 
                                        color: #2d3748; 
                                        line-height: 1.6; 
                                        background: #f7fafc; 
                                        margin: 0; 
                                        padding: 20px;
                                    }
                                    .container { 
                                        max-width: 100%; 
                                        margin: 0 auto; 
                                    }
                                    .header { 
                                        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
                                        border-radius: 16px;
                                        padding: 30px 20px;
                                        margin-bottom: 20px;
                                        text-align: center;
                                        color: white;
                                    }
                                    .alert-card { 
                                        background: white;
                                        border-radius: 16px;
                                        padding: 24px;
                                        margin-bottom: 16px;
                                        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
                                        border-left: 6px solid;
                                    }
                                    .stats-grid { 
                                        display: block;
                                        width: 100%;
                                    }
                                    .stat-item { 
                                        background: #f8fafc;
                                        border-radius: 12px;
                                        padding: 20px;
                                        margin-bottom: 12px;
                                        text-align: center;
                                        border: 1px solid #e2e8f0;
                                    }
                                    .progress-bar { 
                                        background: #e2e8f0;
                                        border-radius: 20px;
                                        height: 12px;
                                        margin: 15px 0;
                                        overflow: hidden;
                                    }
                                    .progress-fill { 
                                        background: linear-gradient(90deg, #f56565, #ed8936);
                                        height: 100%;
                                        border-radius: 20px;
                                    }
                                    .btn { 
                                        display: block;
                                        background: linear-gradient(135deg, #4299e1, #3182ce);
                                        color: white;
                                        padding: 18px;
                                        border-radius: 12px;
                                        text-decoration: none;
                                        font-weight: 600;
                                        text-align: center;
                                        margin: 20px 0;
                                        font-size: 16px;
                                    }
                                    .login-step { 
                                        background: #f7fafc;
                                        border-radius: 12px;
                                        padding: 16px;
                                        margin-bottom: 12px;
                                        border-left: 4px solid #4299e1;
                                    }
                                    @media only screen and (max-width: 600px) {
                                        .alert-card { padding: 20px; margin-bottom: 12px; }
                                        .header { padding: 25px 15px; }
                                        .stat-item { padding: 16px; }
                                    }
                                </style>
                            </head>
                            <body>

                            <div class='container'>

                                <!-- Header Section -->
                                <div class='header'>
                                    <h1 style='font-size: 28px; font-weight: 700; margin: 0 0 8px 0;'>📊 Attendance Alert</h1>
                                    <p style='font-size: 16px; margin: 0; opacity: 0.9;'>SIETK College of Artificial Intelligence</p>
                                </div>

                                <!-- Student Greeting -->
                                <div class='alert-card' style='border-left-color: #4299e1; background: linear-gradient(135deg, #ebf4ff, #c3dafe);'>
                                    <p style='margin: 0; font-size: 18px; color: #2b6cb0; font-weight: 600; text-align: center;'>
                                        👋 Hello, <span style='color: #2c5282;'>{$stu['full_name']}</span>
                                    </p>
                                </div>

                                <!-- Critical Alert -->
                                <div class='alert-card' style='border-left-color: #e53e3e; background: #fff5f5;'>
                                    <table width='100%'>
                                        <tr>
                                            <td width='60' style='vertical-align: top;'>
                                                <span style='font-size: 24px;'>⚠️</span>
                                            </td>
                                            <td>
                                                <h2 style='color: #c53030; font-size: 18px; font-weight: 700; margin: 0 0 4px 0;'>Attention Required</h2>
                                                <p style='color: #718096; font-size: 14px; margin: 0;'>Your attendance is below the required 75% threshold</p>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Monthly Performance -->
                                <div class='alert-card' style='border-left-color: #38a169;'>
                                    <h2 style='color: #22543d; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>📅 Monthly Performance - " .
                                        (function () use ($upload_month) {
                                            $month_names = [
                                                '01' => 'January',
                                                '02' => 'February',
                                                '03' => 'March',
                                                '04' => 'April',
                                                '05' => 'May',
                                                '06' => 'June',
                                                '07' => 'July',
                                                '08' => 'August',
                                                '09' => 'September',
                                                '10' => 'October',
                                                '11' => 'November',
                                                '12' => 'December'
                                            ];
                                            $year = substr($upload_month, 0, 4);
                                            $month_num = substr($upload_month, 5, 2);
                                            return ($month_names[$month_num] ?? $upload_month) . ' ' . $year;
                                        })() . "</h2>

                                    <div class='stats-grid'>
                                        <div class='stat-item'>
                                            <span style='font-size: 14px; color: #718096;'>Current Attendance</span>
                                            <div style='font-size: 32px; font-weight: 800; color: #e53e3e; margin: 8px 0;'>{$percent}%</div>
                                            <div class='progress-bar'>
                                                <div class='progress-fill' style='width: {$percent}%;'></div>
                                            </div>
                                            <span style='font-size: 12px; color: #a0aec0;'>Target: 75% | Deficit: " . (75 - $percent) . "%</span>
                                        </div>
                                    </div>
                                </div>

                                <!-- Attendance Details -->
                                <div class='alert-card' style='border-left-color: #d69e2e;'>
                                    <h2 style='color: #744210; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>📚 Class Statistics</h2>

                                    <div class='stats-grid'>
                                        <div class='stat-item'>
                                            <span style='font-size: 32px; display: block; margin-bottom: 8px;'>📖</span>
                                            <span style='font-size: 14px; color: #718096;'>Classes Conducted</span>
                                            <div style='font-size: 24px; font-weight: 700; color: #2d3748; margin-top: 4px;'>{$classes_conducted}</div>
                                        </div>

                                        <div class='stat-item'>
                                            <span style='font-size: 32px; display: block; margin-bottom: 8px;'>✅</span>
                                            <span style='font-size: 14px; color: #718096;'>Classes Attended</span>
                                            <div style='font-size: 24px; font-weight: 700; color: #38a169; margin-top: 4px;'>{$classes_attended}</div>
                                        </div>

                                        <div class='stat-item'>
                                            <span style='font-size: 32px; display: block; margin-bottom: 8px;'>❌</span>
                                            <span style='font-size: 14px; color: #718096;'>Classes Missed</span>
                                            <div style='font-size: 24px; font-weight: 700; color: #e53e3e; margin-top: 4px;'>" . ($classes_conducted - $classes_attended) . "</div>
                                        </div>
                                    </div>
                                </div>

                                <!-- Action Plan -->
                                <div class='alert-card' style='border-left-color: #ed8936; background: #fffaf0;'>
                                    <table width='100%'>
                                        <tr>
                                            <td width='60' style='vertical-align: top;'>
                                                <span style='font-size: 24px;'>🎯</span>
                                            </td>
                                            <td>
                                                <h2 style='color: #744210; font-size: 18px; font-weight: 700; margin: 0 0 8px 0;'>Required Action</h2>
                                                <p style='color: #744210; margin: 0; font-size: 15px;'>
                                                    Attend <strong>" . max(0, ceil((75 * $classes_conducted / 100) - $classes_attended)) . " more classes</strong> to reach 75% attendance target.
                                                </p>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Overall Performance -->
                                <div class='alert-card' style='border-left-color: #805ad5; background: linear-gradient(135deg, #e9d8fd, #d6bcfa);'>
                                    <table width='100%'>
                                        <tr>
                                            <td>
                                                <span style='font-size: 14px; color: #553c9a; font-weight: 600;'>📊 Overall Attendance</span>
                                                <div style='font-size: 28px; font-weight: 800; color: #44337a;'>{$overall_percentage}%</div>
                                            </td>
                                            <td width='60' style='text-align: right;'>
                                                <span style='font-size: 32px;'>📈</span>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Quick Access -->
                                <div class='alert-card' style='border-left-color: #3182ce;'>
                                    <h2 style='color: #2c5282; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>🔗 Quick Access</h2>

                                    <a href='https://sietkcai.infinityfreeapp.com/' class='btn'>
                                        🌐 Access Student Portal
                                    </a>

                                    <table width='100%'>
                                        <tr>
                                            <td style='padding: 12px 0; border-bottom: 1px solid #e2e8f0;'>
                                                <span style='color: #4a5568; font-size: 14px;'>📧 Support Email</span>
                                            </td>
                                            <td style='padding: 12px 0; border-bottom: 1px solid #e2e8f0; text-align: right;'>
                                                <a href='mailto:caiofficial03@gmail.com' style='color: #e53e3e; text-decoration: none; font-weight: 600;'>caiofficial03@gmail.com</a>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Login Guide -->
                                <div class='alert-card' style='border-left-color: #48bb78;'>
                                    <h2 style='color: #22543d; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>🔐 Login Credentials</h2>

                                    <div class='login-step'>
                                        <strong>👨‍🎓 Regular Students:</strong>
                                        <div style='color: #2f855a; font-weight: 600; margin-top: 4px;'>password</div>
                                    </div>

                                    <div class='login-step'>
                                        <strong>👩‍🎓 LE Students:</strong>
                                        <div style='color: #c05621; font-weight: 600; margin-top: 4px;'>2005-01-01</div>
                                    </div>
                                </div>

                                <!-- Footer -->
                                <div class='alert-card' style='border-left-color: #a0aec0; background: #f7fafc; text-align: center;'>
                                    <p style='color: #718096; font-size: 16px; margin: 0 0 8px 0;'>
                                        🤝 <strong>Best Regards,</strong>
                                    </p>
                                    <p style='color: #4299e1; font-weight: 700; font-size: 18px; margin: 0 0 12px 0;'>
                                        CAI Admin Team
                                    </p>
                                    <p style='color: #a0aec0; font-size: 14px; margin: 0;'>
                                        SIETK College of Artificial Intelligence
                                    </p>
                                </div>

                                <!-- Watermark -->
                                <div style='text-align: center; margin-top: 24px; padding: 16px 0;'>
                                    <p style='color: #a0aec0; font-size: 12px; margin: 0;'>
                                        This is an automated attendance alert. Please do not reply to this email.
                                    </p>
                                </div>

                            </div>

                            </body>
                            </html>";

                                    // Email
                                    if (!empty($stu['email'])) {
                                        require_once 'includes/PHPMailer/PHPMailer.php';
                                        require_once 'includes/PHPMailer/SMTP.php';
                                        require_once 'includes/PHPMailer/Exception.php';
                                        $mail = new \PHPMailer\PHPMailer\PHPMailer(true);
                                        try {
                                            $mail->isSMTP();
                                            $mail->Host = env('SMTP_HOST', 'smtp.gmail.com');
                                            $mail->SMTPAuth = true;
                                            $mail->Username = env('SMTP_USERNAME', '');
                                            $mail->Password = env('SMTP_PASSWORD', '');
                                            $mail->SMTPSecure = \PHPMailer\PHPMailer\PHPMailer::ENCRYPTION_STARTTLS;
                                            $mail->Port = (int) env('SMTP_PORT', 587);
                                            $mail->setFrom(env('SMTP_FROM', env('SMTP_USERNAME', '')), env('SMTP_FROM_NAME', 'CAI Admin'));
                                            $mail->addAddress($stu['email'], $stu['full_name']);
                                            $mail->Subject = 'Attendance Alert: Low Attendance Percentage';
                                            $mail->Body = $bodyText;
                                            $mail->isHTML(true);
                                            $mail->send();
                                        } catch (\Exception $e) {
                                            error_log("Email sending failed for student ID: {$stu_id}. Error: " . $e->getMessage());
                                        }
                                    }
                                }
                            }

                            // Notification if above or equal to 75% (Good performance)
                            if ($percent >= 75) {
                                $stmtStu = $pdo->prepare("SELECT full_name, email, phone FROM students WHERE id = ?");
                                $stmtStu->execute([$stu_id]);
                                $stu = $stmtStu->fetch(PDO::FETCH_ASSOC);

                                if ($stu) {
                                    // Calculate overall percentage
                                    $stmtOverall = $pdo->prepare("SELECT SUM(classes_attended) as attended, SUM(classes_conducted) as conducted FROM attendance_percentage WHERE student_id = ?");
                                    $stmtOverall->execute([$stu_id]);
                                    $overall = $stmtOverall->fetch(PDO::FETCH_ASSOC);
                                    $overall_percentage = ($overall && $overall['conducted'] > 0) ? round(($overall['attended'] / $overall['conducted']) * 100, 2) : 'N/A';

                                    $bodyText = "
                            <html>
                            <head>
                                <meta name='viewport' content='width=device-width, initial-scale=1.0'>
                                <style>
                                    @import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');
                                    body { 
                                        font-family: 'Inter', 'Segoe UI', Arial, sans-serif; 
                                        color: #2d3748; 
                                        line-height: 1.6; 
                                        background: #f7fafc; 
                                        margin: 0; 
                                        padding: 20px;
                                    }
                                    .container { 
                                        max-width: 100%; 
                                        margin: 0 auto; 
                                    }
                                    .header { 
                                        background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
                                        border-radius: 16px;
                                        padding: 30px 20px;
                                        margin-bottom: 20px;
                                        text-align: center;
                                        color: white;
                                    }
                                    .alert-card { 
                                        background: white;
                                        border-radius: 16px;
                                        padding: 24px;
                                        margin-bottom: 16px;
                                        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
                                        border-left: 6px solid;
                                    }
                                    .stats-grid { 
                                        display: block;
                                        width: 100%;
                                    }
                                    .stat-item { 
                                        background: #f8fafc;
                                        border-radius: 12px;
                                        padding: 20px;
                                        margin-bottom: 12px;
                                        text-align: center;
                                        border: 1px solid #e2e8f0;
                                    }
                                    .progress-bar { 
                                        background: #e2e8f0;
                                        border-radius: 20px;
                                        height: 12px;
                                        margin: 15px 0;
                                        overflow: hidden;
                                    }
                                    .progress-fill { 
                                        background: linear-gradient(90deg, #48bb78, #38a169);
                                        height: 100%;
                                        border-radius: 20px;
                                    }
                                    .btn { 
                                        display: block;
                                        background: linear-gradient(135deg, #48bb78, #38a169);
                                        color: white;
                                        padding: 18px;
                                        border-radius: 12px;
                                        text-decoration: none;
                                        font-weight: 600;
                                        text-align: center;
                                        margin: 20px 0;
                                        font-size: 16px;
                                    }
                                    .login-step { 
                                        background: #f7fafc;
                                        border-radius: 12px;
                                        padding: 16px;
                                        margin-bottom: 12px;
                                        border-left: 4px solid #48bb78;
                                    }
                                    .achievement-badge {
                                        background: linear-gradient(135deg, #f6e05e, #ecc94b);
                                        color: #744210;
                                        padding: 8px 16px;
                                        border-radius: 20px;
                                        font-weight: 600;
                                        font-size: 14px;
                                        display: inline-block;
                                        margin: 8px 0;
                                    }
                                    @media only screen and (max-width: 600px) {
                                        .alert-card { padding: 20px; margin-bottom: 12px; }
                                        .header { padding: 25px 15px; }
                                        .stat-item { padding: 16px; }
                                    }
                                </style>
                            </head>
                            <body>

                            <div class='container'>

                                <!-- Header Section -->
                                <div class='header'>
                                    <h1 style='font-size: 28px; font-weight: 700; margin: 0 0 8px 0;'>🎉 Attendance Excellence</h1>
                                    <p style='font-size: 16px; margin: 0; opacity: 0.9;'>SIETK College of Artificial Intelligence</p>
                                </div>

                                <!-- Student Greeting -->
                                <div class='alert-card' style='border-left-color: #48bb78; background: linear-gradient(135deg, #f0fff4, #c6f6d5);'>
                                    <p style='margin: 0; font-size: 18px; color: #22543d; font-weight: 600; text-align: center;'>
                                        👋 Hello, <span style='color: #22543d;'>{$stu['full_name']}</span>
                                    </p>
                                </div>

                                <!-- Success Alert -->
                                <div class='alert-card' style='border-left-color: #48bb78; background: #f0fff4;'>
                                    <table width='100%'>
                                        <tr>
                                            <td width='60' style='vertical-align: top;'>
                                                <span style='font-size: 24px;'>✅</span>
                                            </td>
                                            <td>
                                                <h2 style='color: #22543d; font-size: 18px; font-weight: 700; margin: 0 0 4px 0;'>Great Job!</h2>
                                                <p style='color: #38a169; font-size: 14px; margin: 0;'>You're meeting the attendance requirements</p>
                                            </td>
                                        </tr>
                                    </table>

                                    <div style='text-align: center; margin-top: 12px;'>
                                        <div class='achievement-badge'>
                                            🏆 Target Achieved - 75%+
                                        </div>
                                    </div>
                                </div>

                                <!-- Monthly Performance -->
                                <div class='alert-card' style='border-left-color: #38a169;'>
                                    <h2 style='color: #22543d; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>📅 Monthly Performance - " .
                                        (function () use ($upload_month) {
                                            $month_names = [
                                                '01' => 'January',
                                                '02' => 'February',
                                                '03' => 'March',
                                                '04' => 'April',
                                                '05' => 'May',
                                                '06' => 'June',
                                                '07' => 'July',
                                                '08' => 'August',
                                                '09' => 'September',
                                                '10' => 'October',
                                                '11' => 'November',
                                                '12' => 'December'
                                            ];
                                            $year = substr($upload_month, 0, 4);
                                            $month_num = substr($upload_month, 5, 2);
                                            return ($month_names[$month_num] ?? $upload_month) . ' ' . $year;
                                        })() . "</h2>

                                    <div class='stats-grid'>
                                        <div class='stat-item'>
                                            <span style='font-size: 14px; color: #718096;'>Current Attendance</span>
                                            <div style='font-size: 32px; font-weight: 800; color: #38a169; margin: 8px 0;'>{$percent}%</div>
                                            <div class='progress-bar'>
                                                <div class='progress-fill' style='width: {$percent}%;'></div>
                                            </div>
                                            <span style='font-size: 12px; color: #a0aec0;'>Target: 75% | Excellent: +" . ($percent - 75) . "%</span>
                                        </div>
                                    </div>
                                </div>

                                <!-- Attendance Details -->
                                <div class='alert-card' style='border-left-color: #38b2ac;'>
                                    <h2 style='color: #234e52; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>📚 Class Statistics</h2>

                                    <div class='stats-grid'>
                                        <div class='stat-item'>
                                            <span style='font-size: 32px; display: block; margin-bottom: 8px;'>📖</span>
                                            <span style='font-size: 14px; color: #718096;'>Classes Conducted</span>
                                            <div style='font-size: 24px; font-weight: 700; color: #2d3748; margin-top: 4px;'>{$classes_conducted}</div>
                                        </div>

                                        <div class='stat-item'>
                                            <span style='font-size: 32px; display: block; margin-bottom: 8px;'>✅</span>
                                            <span style='font-size: 14px; color: #718096;'>Classes Attended</span>
                                            <div style='font-size: 24px; font-weight: 700; color: #38a169; margin-top: 4px;'>{$classes_attended}</div>
                                        </div>

                                        <div class='stat-item'>
                                            <span style='font-size: 32px; display: block; margin-bottom: 8px;'>⭐</span>
                                            <span style='font-size: 14px; color: #718096;'>Attendance Streak</span>
                                            <div style='font-size: 24px; font-weight: 700; color: #d69e2e; margin-top: 4px;'>Excellent</div>
                                        </div>
                                    </div>
                                </div>

                                <!-- Achievement Recognition -->
                                <div class='alert-card' style='border-left-color: #d69e2e; background: #fffaf0;'>
                                    <table width='100%'>
                                        <tr>
                                            <td width='60' style='vertical-align: top;'>
                                                <span style='font-size: 24px;'>🏅</span>
                                            </td>
                                            <td>
                                                <h2 style='color: #744210; font-size: 18px; font-weight: 700; margin: 0 0 8px 0;'>Achievement Unlocked</h2>
                                                <p style='color: #744210; margin: 0; font-size: 15px;'>
                                                    You've maintained <strong>" . ($percent - 75) . "% above</strong> the required attendance threshold. Keep up the great work!
                                                </p>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Overall Performance -->
                                <div class='alert-card' style='border-left-color: #805ad5; background: linear-gradient(135deg, #e9d8fd, #d6bcfa);'>
                                    <table width='100%'>
                                        <tr>
                                            <td>
                                                <span style='font-size: 14px; color: #553c9a; font-weight: 600;'>📊 Overall Attendance</span>
                                                <div style='font-size: 28px; font-weight: 800; color: #44337a;'>{$overall_percentage}%</div>
                                            </td>
                                            <td width='60' style='text-align: right;'>
                                                <span style='font-size: 32px;'>📈</span>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Maintenance Tip -->
                                <div class='alert-card' style='border-left-color: #4299e1; background: #ebf8ff;'>
                                    <table width='100%'>
                                        <tr>
                                            <td width='60' style='vertical-align: top;'>
                                                <span style='font-size: 24px;'>💡</span>
                                            </td>
                                            <td>
                                                <h2 style='color: #2b6cb0; font-size: 18px; font-weight: 700; margin: 0 0 8px 0;'>Keep It Up!</h2>
                                                <p style='color: #2b6cb0; margin: 0; font-size: 15px;'>
                                                    Continue your excellent attendance streak to maintain academic excellence and build strong learning habits.
                                                </p>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Quick Access -->
                                <div class='alert-card' style='border-left-color: #3182ce;'>
                                    <h2 style='color: #2c5282; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>🔗 Quick Access</h2>

                                    <a href='https://sietkcai.infinityfreeapp.com/' class='btn'>
                                        🌐 Access Student Portal
                                    </a>

                                    <table width='100%'>
                                        <tr>
                                            <td style='padding: 12px 0; border-bottom: 1px solid #e2e8f0;'>
                                                <span style='color: #4a5568; font-size: 14px;'>📧 Support Email</span>
                                            </td>
                                            <td style='padding: 12px 0; border-bottom: 1px solid #e2e8f0; text-align: right;'>
                                                <a href='mailto:caiofficial03@gmail.com' style='color: #4299e1; text-decoration: none; font-weight: 600;'>caiofficial03@gmail.com</a>
                                            </td>
                                        </tr>
                                    </table>
                                </div>

                                <!-- Login Guide -->
                                <div class='alert-card' style='border-left-color: #48bb78;'>
                                    <h2 style='color: #22543d; font-size: 18px; font-weight: 700; margin: 0 0 16px 0;'>🔐 Login Credentials</h2>

                                    <div class='login-step'>
                                        <strong>👨‍🎓 Regular Students:</strong>
                                        <div style='color: #2f855a; font-weight: 600; margin-top: 4px;'>password</div>
                                    </div>

                                    <div class='login-step'>
                                        <strong>👩‍🎓 LE Students:</strong>
                                        <div style='color: #c05621; font-weight: 600; margin-top: 4px;'>2005-01-01</div>
                                    </div>
                                </div>

                                <!-- Footer -->
                                <div class='alert-card' style='border-left-color: #a0aec0; background: #f7fafc; text-align: center;'>
                                    <p style='color: #718096; font-size: 16px; margin: 0 0 8px 0;'>
                                        🤝 <strong>Best Regards,</strong>
                                    </p>
                                    <p style='color: #48bb78; font-weight: 700; font-size: 18px; margin: 0 0 12px 0;'>
                                        CAI Admin Team
                                    </p>
                                    <p style='color: #a0aec0; font-size: 14px; margin: 0;'>
                                        SIETK College of Artificial Intelligence
                                    </p>
                                </div>

                                <!-- Watermark -->
                                <div style='text-align: center; margin-top: 24px; padding: 16px 0;'>
                                    <p style='color: #a0aec0; font-size: 12px; margin: 0;'>
                                        This is an automated attendance report. Please do not reply to this email.
                                    </p>
                                </div>

                            </div>

                            </body>
                            </html>";

                                    // Email for above 75%
                                    if (!empty($stu['email'])) {
                                        require_once 'includes/PHPMailer/PHPMailer.php';
                                        require_once 'includes/PHPMailer/SMTP.php';
                                        require_once 'includes/PHPMailer/Exception.php';
                                        $mail = new \PHPMailer\PHPMailer\PHPMailer(true);
                                        try {
                                            $mail->isSMTP();
                                            $mail->Host = env('SMTP_HOST', 'smtp.gmail.com');
                                            $mail->SMTPAuth = true;
                                            $mail->Username = env('SMTP_USERNAME', '');
                                            $mail->Password = env('SMTP_PASSWORD', '');
                                            $mail->SMTPSecure = \PHPMailer\PHPMailer\PHPMailer::ENCRYPTION_STARTTLS;
                                            $mail->Port = (int) env('SMTP_PORT', 587);
                                            $mail->setFrom(env('SMTP_FROM', env('SMTP_USERNAME', '')), env('SMTP_FROM_NAME', 'CAI Admin'));
                                            $mail->addAddress($stu['email'], $stu['full_name']);
                                            $mail->Subject = 'Congratulations! Excellent Attendance Record';
                                            $mail->Body = $bodyText;
                                            $mail->isHTML(true);
                                            $mail->send();
                                        } catch (\Exception $e) {
                                            error_log("Email sending failed for student ID: {$stu_id}. Error: " . $e->getMessage());
                                        }
                                    }
                                }
                            }


                            // WhatsApp Message Sending Function using Meta WhatsApp Cloud API
                            if (!function_exists('sendWhatsAppMessage')) {
                                function sendWhatsAppMessage($phone, $message)
                                {
                                    try {
                                        // WhatsApp Cloud API Configuration
$phone_number_id = env('WHATSAPP_PHONE_NUMBER_ID', '');
    $access_token = env('WHATSAPP_ACCESS_TOKEN', '');

                                        // API endpoint
                                        $api_url = "https://graph.facebook.com/v17.0/{$phone_number_id}/messages";

                                        // Remove non-numeric characters
                                        $phone = preg_replace('/[^0-9]/', '', $phone);

                                        // Ensure +91
                                        if (strlen($phone) == 10) {
                                            $phone = '91' . $phone;
                                        }

                                        // Prepare JSON payload
                                        $data = [
                                            "messaging_product" => "whatsapp",
                                            "to" => $phone,
                                            "type" => "text",
                                            "text" => [
                                                "body" => $message
                                            ]
                                        ];

                                        // Headers
                                        $headers = [
                                            "Authorization: Bearer " . $access_token,
                                            "Content-Type: application/json"
                                        ];

                                        // cURL call
                                        $ch = curl_init();
                                        curl_setopt($ch, CURLOPT_URL, $api_url);
                                        curl_setopt($ch, CURLOPT_POST, 1);
                                        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data));
                                        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
                                        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
                                        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

                                        $response = curl_exec($ch);
                                        $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
                                        $curl_error = curl_error($ch);
                                        curl_close($ch);

                                        error_log("WA API - HTTP: {$http_code}, Response: {$response}");

                                        return ($http_code == 200);
                                    } catch (Exception $e) {
                                        error_log("WA Error ({$phone}): " . $e->getMessage());
                                        return false;
                                    }
                                }
                            }



                            // WhatsApp Alert for Low Attendance (below 75%)
                            if ($percent < 75) {
                                $stmtStu = $pdo->prepare("SELECT full_name, phone FROM students WHERE id = ?");
                                $stmtStu->execute([$stu_id]);
                                $stu = $stmtStu->fetch(PDO::FETCH_ASSOC);

                                if ($stu && !empty($stu['phone'])) {
                                    // Calculate overall percentage
                                    $stmtOverall = $pdo->prepare("SELECT SUM(classes_attended) as attended, SUM(classes_conducted) as conducted FROM attendance_percentage WHERE student_id = ?");
                                    $stmtOverall->execute([$stu_id]);
                                    $overall = $stmtOverall->fetch(PDO::FETCH_ASSOC);
                                    $overall_percentage = ($overall && $overall['conducted'] > 0) ? round(($overall['attended'] / $overall['conducted']) * 100, 2) : 'N/A';

                                    $month_name = date('F Y', strtotime($upload_month . '-01'));
                                    $classes_missed = $classes_conducted - $classes_attended;
                                    $required_classes = max(0, ceil((75 * $classes_conducted / 100) - $classes_attended));

                                    $whatsapp_message = "🎓 *ATTENDANCE NOTIFICATION - SIETK CAI*\n\n"
                                        . "Dear {$stu['full_name']},\n\n"
                                        . "📊 *MONTHLY ATTENDANCE REPORT*\n"
                                        . "• Month: {$month_name}\n"
                                        . "• Attendance Percentage: *{$percent}%*\n"
                                        . "• Classes Conducted: {$classes_conducted}\n"
                                        . "• Classes Attended: {$classes_attended}\n"
                                        . "• Classes Missed: " . ($classes_conducted - $classes_attended) . "\n\n"
                                        . "⚠️ *ATTENTION REQUIRED*\n"
                                        . "Your attendance is below the required 75% threshold.\n\n"
                                        . "🎯 *IMMEDIATE ACTION NEEDED*\n"
                                        . "You need to attend *{$required_classes} more classes* to reach the 75% target.\n\n"
                                        . "📅 *DAYS CALCULATION TO REACH 75%*\n"
                                        . "• Assuming 6 classes per day: *" . ceil($required_classes / 6) . " days*\n"
                                        . "• Assuming 5 classes per day: *" . ceil($required_classes / 5) . " days*\n"
                                        . "• Assuming 4 classes per day: *" . ceil($required_classes / 4) . " days*\n\n"
                                        . "📈 *OVERALL PERFORMANCE*\n"
                                        . "Cumulative Attendance: {$overall_percentage}%\n\n"
                                        . "🔗 *ACCESS YOUR PORTAL*\n"
                                        . "Website: https://sietkcai.infinityfreeapp.com/\n\n"
                                        . "🔐 *LOGIN CREDENTIALS*\n"
                                        . "Username: Your Roll Number\n"
                                        . "Default Password: password\n\n"
                                        . "📱 *VIEW ATTENDANCE*\n"
                                        . "After login, navigate to 'Attendance' section to view detailed reports.\n\n"
                                        . "💡 *IMPORTANT NOTES*\n"
                                        . "• Regular attendance is crucial for academic success\n"
                                        . "• Maintain above 75% to avoid academic consequences\n"
                                        . "• Contact admin for password reset assistance\n\n"
                                        . "📞 *SUPPORT CONTACT*\n"
                                        . "Email: caiofficial03@gmail.com\n\n"
                                        . "Best Regards,\n"
                                        . "CAI Administration\n"
                                        . "SIETK College of Artificial Intelligence";

                                    // Send WhatsApp message using WhatsApp Cloud API
                                    sendWhatsAppMessage($stu['phone'], $whatsapp_message);
                                }
                            }


                            // WhatsApp Alert for Excellent Attendance (above/equal to 75%)
                            if ($percent >= 75) {
                                $stmtStu = $pdo->prepare("SELECT full_name, phone FROM students WHERE id = ?");
                                $stmtStu->execute([$stu_id]);
                                $stu = $stmtStu->fetch(PDO::FETCH_ASSOC);

                                if ($stu && !empty($stu['phone'])) {
                                    // Calculate overall percentage
                                    $stmtOverall = $pdo->prepare("SELECT SUM(classes_attended) as attended, SUM(classes_conducted) as conducted FROM attendance_percentage WHERE student_id = ?");
                                    $stmtOverall->execute([$stu_id]);
                                    $overall = $stmtOverall->fetch(PDO::FETCH_ASSOC);
                                    $overall_percentage = ($overall && $overall['conducted'] > 0) ? round(($overall['attended'] / $overall['conducted']) * 100, 2) : 'N/A';

                                    $month_name = date('F Y', strtotime($upload_month . '-01'));
                                    $above_target = $percent - 75;

                                    $whatsapp_message = "🎓 *ATTENDANCE EXCELLENCE - SIETK CAI*\n\n"
                                        . "Dear {$stu['full_name']},\n\n"
                                        . "🏆 *OUTSTANDING PERFORMANCE*\n"
                                        . "Congratulations on maintaining excellent attendance!\n\n"
                                        . "📊 *MONTHLY ATTENDANCE REPORT*\n"
                                        . "• Month: {$month_name}\n"
                                        . "• Attendance Percentage: *{$percent}%* ✅\n"
                                        . "• Classes Conducted: {$classes_conducted}\n"
                                        . "• Classes Attended: {$classes_attended}\n"
                                        . "• Above Target: +" . ($percent - 75) . "%\n\n"
                                        . "⭐ *ACHIEVEMENT UNLOCKED*\n"
                                        . "You have successfully exceeded the 75% attendance requirement!\n\n"
                                        . "📈 *OVERALL PERFORMANCE*\n"
                                        . "Cumulative Attendance: {$overall_percentage}%\n\n"
                                        . "🎯 *MAINTAIN YOUR STREAK*\n"
                                        . "• Continue your excellent attendance record\n"
                                        . "• Your consistency is commendable\n"
                                        . "• Keep up the great work!\n\n"
                                        . "🔗 *ACCESS YOUR PORTAL*\n"
                                        . "Website: https://sietkcai.infinityfreeapp.com/\n\n"
                                        . "📱 *VIEW YOUR PROGRESS*\n"
                                        . "Login to check your detailed attendance analytics and performance trends.\n\n"
                                        . "💡 *SUCCESS TIPS*\n"
                                        . "• Maintain this excellent streak throughout the semester\n"
                                        . "• Your dedication reflects in your academic performance\n"
                                        . "• Share your success strategies with peers\n\n"
                                        . "🎉 *WELL DONE!*\n"
                                        . "Your commitment to regular attendance is truly appreciated and recognized.\n\n"
                                        . "Best Regards,\n"
                                        . "CAI Administration\n"
                                        . "SIETK College of Artificial Intelligence";

                                    // Send WhatsApp message using WhatsApp Cloud API
                                    sendWhatsAppMessage($stu['phone'], $whatsapp_message);
                                }
                            }
                        }
                    }
                    echo '<script>alert("Attendance percentages saved successfully.");</script>';
                }
                ?>

                <hr style="margin:2rem 0;">
                <h3>View Attendance Summary</h3>
                <form id="attendanceSummaryForm" style="margin-bottom:1.5rem;">
                    <label class="form-label">Select Month: </label>
                    <input type="month" id="attendance_month_input"
                        value="<?php echo date('Y-m'); ?>">
                    <button type="button" id="viewAttendanceBtn" class="btn" style="padding:0.4rem 1.2rem;">View</button>
                    <button type="button" id="closeAttendanceBtn" class="btn" style="padding:0.4rem 1.2rem; background:#999; display:none;">Close</button>
                </form>

                <!-- Container for attendance summary (initially hidden) -->
                <div id="attendance-summary-container" style="display:none; overflow-x:auto;">
                    <table class="modern-table" id="attendance-summary-table">
                        <thead>
                            <tr>
                                <th rowspan="2" style="text-align: center;">Roll No</th>
                                <th rowspan="2" style="text-align: center;">Name</th>
                                <th colspan="3" style="text-align: center;" id="month-header">
                                    <!-- Month will be inserted here by JS -->
                                </th>
                                <th rowspan="2" style="text-align: center;">Overall %</th>
                            </tr>
                            <tr>
                                <th style="text-align: center;">No. of Classes Conducted</th>
                                <th style="text-align: center;">No. of Classes Attended</th>
                                <th style="text-align: center;">Percentage</th>
                            </tr>
                        </thead>
                        <tbody id="attendance-summary-tbody">
                            <!-- Data will be inserted here by JS -->
                        </tbody>
                    </table>
                </div>
                <div id="attendance-loading" style="display:none; text-align:center; padding:2rem;">
                    <p>Loading attendance data...</p>
                </div>
            </div>

            <!-- Manage Faculty Section -->
            <div id="manage-faculty" class="content-subsection">
                <h3>Manage Faculty</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 2rem;">
                    <h4>Add New Faculty</h4>

                    <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                        <div class="form-group">
                            <label class="form-label">Full Name</label>
                            <input type="text" name="full_name" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Subject</label>
                            <input type="text" name="subject" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Qualification</label>
                            <input type="text" name="qualification" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Email</label>
                            <input type="email" name="email" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Phone</label>
                            <input type="text" name="phone" class="form-input">
                        </div>

                        <div class="form-group">
                            <label class="form-label">Profile Image</label>
                            <input type="file" name="profile_image" class="form-input" accept="image/*">
                        </div>

                        <div class="form-group">
                            <label class="form-label" style="display: flex; align-items: center;">
                                <input type="checkbox" name="is_hod" style="margin-right: 0.5rem;">
                                Is HOD
                            </label>
                        </div>

                        <div class="form-group">
                            <label class="form-label" style="display: flex; align-items: center;">
                                <input type="checkbox" name="is_counsellor" style="margin-right: 0.5rem;">
                                Is Counsellor
                            </label>
                        </div>

                    </div>

                    <button type="submit" name="add_faculty" class="btn">Add Faculty</button>
                </form>

                <h4>Existing Faculty</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Name</th>
                                <th>Subject</th>
                                <th>Email</th>
                                <th>HOD</th>
                                <th>Counsellor</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM faculty");
                            $faculty = $stmt->fetchAll(PDO::FETCH_ASSOC);

                            foreach ($faculty as $member) {
                                echo '<tr>';
                                echo '<td>' . $member['id'] . '</td>';
                                echo '<td>' . $member['full_name'] . '</td>';
                                echo '<td>' . $member['subject'] . '</td>';
                                echo '<td>' . $member['email'] . '</td>';
                                echo '<td>' . ($member['is_hod'] ? 'Yes' : 'No') . '</td>';
                                echo '<td>' . ($member['is_counsellor'] ? 'Yes' : 'No') . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=faculty&id=' . $member['id'] . '#manage-faculty" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=faculty&id=' . $member['id'] . '" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this faculty member?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
                <?php
                // Show edit form if editing faculty
                if (isset($_GET['edit']) && $_GET['type'] === 'faculty' && isset($_GET['id'])) {
                    $edit_id = $_GET['id'];
                    $stmt = $pdo->prepare("SELECT * FROM faculty WHERE id = ?");
                    $stmt->execute([$edit_id]);
                    $edit_faculty = $stmt->fetch(PDO::FETCH_ASSOC);
                    if ($edit_faculty) {
                ?>
                        <form method="POST" enctype="multipart/form-data"
                            style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                            <h4>Edit Faculty (ID: <?php echo $edit_faculty['id']; ?>)</h4>
                            <input type="hidden" name="faculty_id" value="<?php echo $edit_faculty['id']; ?>">
                            <input type="hidden" name="existing_profile_image"
                                value="<?php echo htmlspecialchars($edit_faculty['profile_image']); ?>">

                            <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                                <div class="form-group">
                                    <label class="form-label">Full Name</label>
                                    <input type="text" name="full_name" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_faculty['full_name']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Subject</label>
                                    <input type="text" name="subject" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_faculty['subject']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Qualification</label>
                                    <input type="text" name="qualification" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_faculty['qualification']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Email</label>
                                    <input type="email" name="email" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_faculty['email']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Phone</label>
                                    <input type="text" name="phone" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_faculty['phone']); ?>">
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Profile Image</label>
                                    <?php if (!empty($edit_faculty['profile_image'])): ?>
                                        <img src="assets/images/faculty/<?php echo htmlspecialchars($edit_faculty['profile_image']); ?>"
                                            alt="Current Image"
                                            style="width:60px; height:60px; border-radius:50%; object-fit:cover; margin-bottom:0.5rem;">
                                    <?php endif; ?>
                                    <input type="file" name="profile_image" class="form-input" accept="image/*">
                                </div>
                                <div class="form-group">
                                    <label class="form-label" style="display: flex; align-items: center;">
                                        <input type="checkbox" name="is_hod" style="margin-right: 0.5rem;" <?php echo $edit_faculty['is_hod'] ? 'checked' : ''; ?>>
                                        Is HOD
                                    </label>
                                </div>
                                <div class="form-group">
                                    <label class="form-label" style="display: flex; align-items: center;">
                                        <input type="checkbox" name="is_counsellor" style="margin-right: 0.5rem;" <?php echo $edit_faculty['is_counsellor'] ? 'checked' : ''; ?>>
                                        Is Counsellor
                                    </label>
                                </div>
                            </div>
                            <button type="submit" name="update_faculty" class="btn">Update Faculty</button>
                            <a href="admin_dashboard.php#manage-faculty" class="btn"
                                style="background:#ccc; color:#333;">Cancel</a>
                        </form>
                <?php
                    }
                }
                ?>
            </div>

            <!-- Manage Students Section -->
            <div id="manage-students" class="content-subsection">
                <h3>Manage Students</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 2rem;">
                    <h4>Add New Student</h4>

                    <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                        <div class="form-group">
                            <label class="form-label">Roll Number</label>
                            <input type="text" name="roll_number" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Full Name</label>
                            <input type="text" name="full_name" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Date of Birth</label>
                            <input type="date" name="date_of_birth" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Email</label>
                            <input type="email" name="email" class="form-input">
                        </div>

                        <div class="form-group">
                            <label class="form-label">Phone</label>
                            <input type="text" name="phone" class="form-input">
                        </div>

                        <div class="form-group">
                            <label class="form-label">Address</label>
                            <textarea name="address" class="form-input" rows="2"></textarea>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Year</label>
                            <select name="year" class="form-input" required>
                                <option value="1">Year 1</option>
                                <option value="2">Year 2</option>
                                <option value="3">Year 3</option>
                                <option value="4">Year 4</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Semester</label>
                            <select name="semester" class="form-input" required>
                                <option value="1">Semester 1</option>
                                <option value="2">Semester 2</option>
                                <option value="3">Semester 3</option>
                                <option value="4">Semester 4</option>
                                <option value="5">Semester 5</option>
                                <option value="6">Semester 6</option>
                                <option value="7">Semester 7</option>
                                <option value="8">Semester 8</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Profile Image</label>
                            <input type="file" name="profile_image" class="form-input" accept="image/*">
                        </div>

                        <div class="form-group">
                            <label class="form-label" style="display: flex; align-items: center;">
                                <input type="checkbox" name="is_cr" style="margin-right: 0.5rem;">
                                Is Class Representative (CR)
                            </label>
                        </div>

                        <div class="form-group">
                            <label class="form-label" style="display: flex; align-items: center;">
                                <input type="checkbox" name="is_lr" style="margin-right: 0.5rem;">
                                Is Ladies Representative (LR)
                            </label>
                        </div>

                        <div class="form-group">
                            <label class="form-label" style="display: flex; align-items: center;">
                                <input type="checkbox" name="is_acr" style="margin-right: 0.5rem;">
                                Is Assistant Class Representative (ACR)
                            </label>
                        </div>

                        <div class="form-group">
                            <label class="form-label" style="display: flex; align-items: center;">
                                <input type="checkbox" name="is_admin_profile" style="margin-right: 0.5rem;">
                                Is Admin Profile
                            </label>
                        </div>
                    </div>

                    <button type="submit" name="add_student" class="btn">Add Student</button>
                </form>

                <h4>Existing Students</h4>
                <div class="existing-table-wrapper">
                    <?php
                    // Show edit form if editing
                    if (isset($_GET['edit']) && $_GET['type'] === 'student' && isset($_GET['id'])) {
                        $edit_id = $_GET['id'];
                        $stmt = $pdo->prepare("SELECT * FROM students WHERE id = ?");
                        $stmt->execute([$edit_id]);
                        $edit_student = $stmt->fetch(PDO::FETCH_ASSOC);
                        if ($edit_student) {
                    ?>
                            <form method="POST" enctype="multipart/form-data"
                                style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                                <h4>Edit Student (ID: <?php echo $edit_student['id']; ?>)</h4>
                                <input type="hidden" name="student_id" value="<?php echo $edit_student['id']; ?>">
                                <input type="hidden" name="existing_profile_image"
                                    value="<?php echo htmlspecialchars($edit_student['profile_image']); ?>">
                                <div
                                    style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                                    <div class="form-group">
                                        <label class="form-label">Roll Number</label>
                                        <input type="text" name="roll_number" class="form-input"
                                            value="<?php echo htmlspecialchars($edit_student['roll_number']); ?>" required>
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Full Name</label>
                                        <input type="text" name="full_name" class="form-input"
                                            value="<?php echo htmlspecialchars($edit_student['full_name']); ?>" required>
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Date of Birth</label>
                                        <input type="date" name="date_of_birth" class="form-input"
                                            value="<?php echo htmlspecialchars($edit_student['date_of_birth']); ?>" required>
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Email</label>
                                        <input type="email" name="email" class="form-input"
                                            value="<?php echo isset($edit_student['email']) ? htmlspecialchars($edit_student['email']) : ''; ?>">
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Phone</label>
                                        <input type="text" name="phone" class="form-input"
                                            value="<?php echo htmlspecialchars($edit_student['phone']); ?>">
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Address</label>
                                        <textarea name="address" class="form-input"
                                            rows="2"><?php echo htmlspecialchars($edit_student['address']); ?></textarea>
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Year</label>
                                        <select name="year" class="form-input" required>
                                            <?php
                                            $currentYear = isset($edit_student['year']) ? $edit_student['year'] : 1;
                                            for ($y = 1; $y <= 4; $y++)
                                                echo '<option value="' . $y . '"' . ($currentYear == $y ? ' selected' : '') . '>Year ' . $y . '</option>';
                                            ?>
                                        </select>
                                    </div>

                                    <div class="form-group">
                                        <label class="form-label">Semester</label>
                                        <select name="semester" class="form-input" required>
                                            <?php
                                            $currentSemester = isset($edit_student['semester']) ? $edit_student['semester'] : 1;
                                            for ($s = 1; $s <= 8; $s++)
                                                echo '<option value="' . $s . '"' . ($currentSemester == $s ? ' selected' : '') . '>Semester ' . $s . '</option>';
                                            ?>
                                        </select>
                                    </div>
                                    <div class="form-group">
                                        <label class="form-label">Profile Image</label>
                                        <?php if (!empty($edit_student['profile_image'])): ?>
                                            <img src="assets/images/students/<?php echo htmlspecialchars($edit_student['profile_image']); ?>"
                                                alt="Current Image"
                                                style="width:60px; height:60px; border-radius:50%; object-fit:cover; margin-bottom:0.5rem;">
                                        <?php endif; ?>
                                        <input type="file" name="profile_image" class="form-input" accept="image/*">
                                    </div>

                                    <div class="form-group">
                                        <label class="form-label" style="display: flex; align-items: center;">
                                            <input type="checkbox" name="is_cr" style="margin-right: 0.5rem;" <?php echo (isset($edit_student['is_cr']) && $edit_student['is_cr']) ? 'checked' : ''; ?>>
                                            Is Class Representative (CR)
                                        </label>
                                    </div>

                                    <div class="form-group">
                                        <label class="form-label" style="display: flex; align-items: center;">
                                            <input type="checkbox" name="is_lr" style="margin-right: 0.5rem;" <?php echo (isset($edit_student['is_lr']) && $edit_student['is_lr']) ? 'checked' : ''; ?>>
                                            Is Ladies Representative (LR)
                                        </label>
                                    </div>

                                    <div class="form-group">
                                        <label class="form-label" style="display: flex; align-items: center;">
                                            <input type="checkbox" name="is_acr" style="margin-right: 0.5rem;" <?php echo (isset($edit_student['is_acr']) && $edit_student['is_acr']) ? 'checked' : ''; ?>>
                                            Is Assistant Class Representative (ACR)
                                        </label>
                                    </div>

                                    <div class="form-group">
                                        <label class="form-label" style="display: flex; align-items: center;">
                                            <input type="checkbox" name="is_admin_profile" style="margin-right: 0.5rem;" <?php echo $edit_student['is_admin_profile'] ? 'checked' : ''; ?>>
                                            Is Admin Profile
                                        </label>
                                    </div>
                                </div>
                                <button type="submit" name="update_student" class="btn">Update Student</button>
                                <a href="admin_dashboard.php#manage-students" class="btn"
                                    style="background:#ccc; color:#333;">Cancel</a>
                            </form>
                    <?php }
                    } ?>
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Roll No</th>
                                <th>Name</th>
                                <th>Email</th>
                                <th>Year</th>
                                <th>Semester</th>
                                <th>CR</th>
                                <th>LR</th>
                                <th>ACR</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            if (!isset($students) || !is_array($students)) {
                                $stmt = $pdo->query("SELECT id, roll_number, full_name, email, year, semester, is_cr, is_lr, is_acr FROM students ORDER BY roll_number");
                                $students = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            }
                            foreach ($students as $student) {
                                echo '<tr>';
                                echo '<td>' . $student['id'] . '</td>';
                                echo '<td>' . $student['roll_number'] . '</td>';
                                echo '<td>' . $student['full_name'] . '</td>';
                                echo '<td>' . (isset($student['email']) ? $student['email'] : '') . '</td>';
                                echo '<td>' . (isset($student['year']) ? $student['year'] : '') . '</td>';
                                echo '<td>' . (isset($student['semester']) ? $student['semester'] : '') . '</td>';
                                echo '<td>' . (isset($student['is_cr']) && $student['is_cr'] ? 'Yes' : 'No') . '</td>';
                                echo '<td>' . (isset($student['is_lr']) && $student['is_lr'] ? 'Yes' : 'No') . '</td>';
                                echo '<td>' . (isset($student['is_acr']) && $student['is_acr'] ? 'Yes' : 'No') . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=student&id=' . $student['id'] . '#manage-students" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=student&id=' . $student['id'] . '" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this student?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
            </div>

            <!-- Manage Timetable Section -->
            <div id="manage-timetable" class="content-subsection">
                <h3>Manage Timetable</h3>

                <!-- Existing timetable entry form (keep) -->
                <form method="POST" style="margin-bottom: 2rem;">
                    <!-- ...existing add timetable fields... -->
                </form>

                <!-- New: Upload/Replace timetable image -->
                <?php
                $timetableDir = 'assets/uploads/timetable/';
                $currentTimetable = null;
                foreach (glob($timetableDir . 'timetable_current.*') as $f) {
                    $currentTimetable = $f;
                    break;
                }
                ?>
                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 1.5rem;">
                    <h4>Upload Timetable Image (will replace current)</h4>
                    <?php if ($currentTimetable): ?>
                        <div style="margin-bottom:0.5rem;">
                            <strong>Current:</strong><br>
                            <img src="<?php echo htmlspecialchars($currentTimetable); ?>" alt="Current Timetable" style="max-width:320px; height:auto; display:block; margin-top:0.5rem; border:1px solid #ddd; padding:4px; border-radius:6px;">
                        </div>
                    <?php else: ?>
                        <div style="margin-bottom:0.5rem;"><em>No timetable image uploaded yet.</em></div>
                    <?php endif; ?>
                    <input type="file" name="timetable_image" accept="image/*" required>
                    <button type="submit" name="upload_timetable_image" class="btn" style="margin-top:0.5rem;">Upload Timetable Image</button>
                </form>
            </div>

            <!-- Manage Syllabus Section -->
            <div id="manage-syllabus" class="content-subsection">
                <h3>Manage Syllabus</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 2rem;">
                    <h4>Add New Syllabus</h4>

                    <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                        <div class="form-group">
                            <label class="form-label">Year</label>
                            <select name="year" class="form-input" required>
                                <option value="1">Year 1</option>
                                <option value="2">Year 2</option>
                                <option value="3">Year 3</option>
                                <option value="4">Year 4</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Semester</label>
                            <select name="semester" class="form-input" required>
                                <option value="1">Semester 1</option>
                                <option value="2">Semester 2</option>
                                <option value="3">Semester 3</option>
                                <option value="4">Semester 4</option>
                                <option value="5">Semester 5</option>
                                <option value="6">Semester 6</option>
                                <option value="7">Semester 7</option>
                                <option value="8">Semester 8</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Subject</label>
                            <input type="text" name="subject" class="form-input" required>
                        </div>
                    </div>

                    <div class="form-group">
                        <label class="form-label">Syllabus Content</label>
                        <textarea name="syllabus_content" class="form-input" rows="10" required></textarea>
                    </div>

                    <div class="form-group">
                        <label class="form-label">Syllabus File (PDF/ZIP)</label>
                        <input type="file" name="syllabus_file" class="form-input" accept=".pdf,.doc,.docx,.docm,.odt,.zip,.rar,.7z">
                    </div>

                    <button type="submit" name="add_syllabus" class="btn">Add Syllabus</button>
                </form>

                <?php
                // In Manage Syllabus section - keep only ONE edit form after the table:
                if (isset($_GET['edit']) && $_GET['type'] === 'syllabus' && isset($_GET['id'])) {
                    $edit_id = $_GET['id'];
                    $stmt = $pdo->prepare("SELECT * FROM syllabus WHERE id = ?");
                    $stmt->execute([$edit_id]);
                    $edit_item = $stmt->fetch(PDO::FETCH_ASSOC);
                    if ($edit_item) {
                ?>
                        <form method="POST" enctype="multipart/form-data"
                            style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                            <h4>Edit Syllabus (ID: <?php echo $edit_item['id']; ?>)</h4>
                            <input type="hidden" name="syllabus_id" value="<?php echo $edit_item['id']; ?>">
                            <input type="hidden" name="existing_file_path"
                                value="<?php echo htmlspecialchars($edit_item['file_path']); ?>">
                            <div
                                style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                                <div class="form-group">
                                    <label class="form-label">Year</label>
                                    <select name="year" class="form-input" required>
                                        <?php for ($y = 1; $y <= 4; $y++): ?>
                                            <option value="<?php echo $y; ?>" <?php echo ($edit_item['year'] == $y) ? 'selected' : ''; ?>>Year <?php echo $y; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Semester</label>
                                    <select name="semester" class="form-input" required>
                                        <?php for ($s = 1; $s <= 8; $s++): ?>
                                            <option value="<?php echo $s; ?>" <?php echo ($edit_item['semester'] == $s) ? 'selected' : ''; ?>>Semester <?php echo $s; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Subject</label>
                                    <input type="text" name="subject" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_item['subject']); ?>" required>
                                </div>
                            </div>
                            <div class="form-group">
                                <label class="form-label">Syllabus Content</label>
                                <textarea name="syllabus_content" class="form-input" rows="10"
                                    required><?php echo htmlspecialchars($edit_item['syllabus_content']); ?></textarea>
                            </div>
                            <div class="form-group">
                                <label class="form-label">Syllabus File (PDF/ZIP)</label>
                                <?php if (!empty($edit_item['file_path'])): ?>
                                    <a href="<?php echo htmlspecialchars($edit_item['file_path']); ?>" target="_blank">Current
                                        File</a><br>
                                <?php endif; ?>
                                <input type="file" name="syllabus_file" class="form-input" accept=".pdf,.zip,.rar,.7zip">
                            </div>
                            <button type="submit" name="update_syllabus" class="btn">Update Syllabus</button>
                            <a href="admin_dashboard.php#manage-syllabus" class="btn"
                                style="background:#ccc; color:#333;">Cancel</a>
                        </form>
                <?php
                    }
                }
                ?>

                <h4>Existing Syllabus</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Year</th>
                                <th>Semester</th>
                                <th>Subject</th>
                                <th>File</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM syllabus ORDER BY year, semester, subject");
                            $syllabus = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            foreach ($syllabus as $item) {
                                echo '<tr>';
                                echo '<td>' . $item['id'] . '</td>';
                                echo '<td>' . $item['year'] . '</td>';
                                echo '<td>' . $item['semester'] . '</td>';
                                echo '<td>' . $item['subject'] . '</td>';
                                echo '<td>';
                                if (!empty($item['file_path'])) {
                                    echo '<a href="' . htmlspecialchars($item['file_path']) . '" target="_blank">Download</a>';
                                } else {
                                    echo 'N/A';
                                }
                                echo '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=syllabus&id=' . $item['id'] . '#manage-syllabus" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=syllabus&id=' . $item['id'] . '" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this syllabus?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
            </div>



            <!-- Manage Study Materials Section -->
            <div id="manage-materials" class="content-subsection">
                <h3>Manage Question Banks</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 2rem;">
                    <h4>Add New Question Bank</h4>

                    <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                        <div class="form-group">
                            <label class="form-label">Year</label>
                            <select name="year" class="form-input" required>
                                <option value="1">Year 1</option>
                                <option value="2">Year 2</option>
                                <option value="3">Year 3</option>
                                <option value="4">Year 4</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Semester</label>
                            <select name="semester" class="form-input" required>
                                <option value="1">Semester 1</option>
                                <option value="2">Semester 2</option>
                                <option value="3">Semester 3</option>
                                <option value="4">Semester 4</option>
                                <option value="5">Semester 5</option>
                                <option value="6">Semester 6</option>
                                <option value="7">Semester 7</option>
                                <option value="8">Semester 8</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Subject</label>
                            <input type="text" name="subject" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Question Bank</label>
                            <input type="file" name="material_file" class="form-input" accept=".pdf,.doc,.docx,.docm,.odt,.zip,.rar,.7z">
                        </div>
                    </div>

                    <button type="submit" name="add_material" class="btn">Add Question Bank</button>
                </form>

                <?php
                // Show edit form if editing
                if (isset($_GET['edit']) && $_GET['type'] === 'material' && isset($_GET['id'])) {
                    $edit_id = $_GET['id'];
                    $stmt = $pdo->prepare("SELECT * FROM study_materials WHERE id = ?");
                    $stmt->execute([$edit_id]);
                    $edit_item = $stmt->fetch(PDO::FETCH_ASSOC);
                    if ($edit_item) {
                ?>
                        <form method="POST" enctype="multipart/form-data"
                            style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                            <h4>Edit Question Bank (ID: <?php echo $edit_item['id']; ?>)</h4>
                            <input type="hidden" name="material_id" value="<?php echo $edit_item['id']; ?>">
                            <input type="hidden" name="existing_file_path"
                                value="<?php echo htmlspecialchars($edit_item['file_path']); ?>">

                            <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                                <div class="form-group">
                                    <label class="form-label">Year</label>
                                    <select name="year" class="form-input" required>
                                        <?php for ($y = 1; $y <= 4; $y++): ?>
                                            <option value="<?php echo $y; ?>" <?php echo ($edit_item['year'] == $y) ? 'selected' : ''; ?>>Year <?php echo $y; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Semester</label>
                                    <select name="semester" class="form-input" required>
                                        <?php for ($s = 1; $s <= 8; $s++): ?>
                                            <option value="<?php echo $s; ?>" <?php echo ($edit_item['semester'] == $s) ? 'selected' : ''; ?>>Semester <?php echo $s; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Subject</label>
                                    <input type="text" name="subject" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_item['subject']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Question Bank File (ZIP/RAR)</label>
                                    <?php if (!empty($edit_item['file_path'])): ?>
                                        <a href="<?php echo htmlspecialchars($edit_item['file_path']); ?>" target="_blank">Current
                                            File</a><br>
                                    <?php endif; ?>
                                    <input type="file" name="material_file" class="form-input" accept=".zip,.rar,.7zip">
                                </div>
                            </div>
                            <button type="submit" name="update_material" class="btn">Update Question Bank</button>
                            <a href="admin_dashboard.php#manage-materials" class="btn"
                                style="background:#ccc; color:#333;">Cancel</a>
                        </form>
                <?php
                    }
                }
                ?>

                <h4>Existing Question Banks</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Year</th>
                                <th>Semester</th>
                                <th>Subject</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM study_materials ORDER BY year, semester, subject");
                            $materials = $stmt->fetchAll(PDO::FETCH_ASSOC);

                            foreach ($materials as $material) {
                                echo '<tr>';
                                echo '<td>' . $material['id'] . '</td>';
                                echo '<td>' . $material['year'] . '</td>';
                                echo '<td>' . $material['semester'] . '</td>';
                                echo '<td>' . $material['subject'] . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=material&id=' . $material['id'] . '#manage-materials" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=material&id=' . $material['id'] . '" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this study material?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
            </div>

            <!-- Manage Bit Bank Section -->
            <div id="manage-bit-bank" class="content-subsection">
                <h3>Manage Bit Bank</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 2rem;">
                    <h4>Add New Bit Bank</h4>

                    <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                        <div class="form-group">
                            <label class="form-label">Year</label>
                            <select name="year" class="form-input" required>
                                <option value="1">Year 1</option>
                                <option value="2">Year 2</option>
                                <option value="3">Year 3</option>
                                <option value="4">Year 4</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Semester</label>
                            <select name="semester" class="form-input" required>
                                <option value="1">Semester 1</option>
                                <option value="2">Semester 2</option>
                                <option value="3">Semester 3</option>
                                <option value="4">Semester 4</option>
                                <option value="5">Semester 5</option>
                                <option value="6">Semester 6</option>
                                <option value="7">Semester 7</option>
                                <option value="8">Semester 8</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Subject</label>
                            <input type="text" name="subject" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Bit Bank File (PDF)</label>
                            <input type="file" name="bit_bank_file" class="form-input" accept=".pdf,.doc,.docx,.docm,.odt">
                        </div>
                    </div>

                    <button type="submit" name="add_bit_bank" class="btn">Add Bit Bank</button>
                </form>

                <h4>Existing Bit Bank</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Year</th>
                                <th>Semester</th>
                                <th>Subject</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM bit_bank ORDER BY year, semester, subject");
                            $bit_bank = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            foreach ($bit_bank as $item) {
                                echo '<tr>';
                                echo '<td>' . $item['id'] . '</td>';
                                echo '<td>' . $item['year'] . '</td>';
                                echo '<td>' . $item['semester'] . '</td>';
                                echo '<td>' . $item['subject'] . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=bit_bank&id=' . $item['id'] . '#manage-bit-bank" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=bit_bank&id=' . $item['id'] . '" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this bit bank?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
                <?php
                // Show edit form if editing bit bank
                if (isset($_GET['edit']) && $_GET['type'] === 'bit_bank' && isset($_GET['id'])) {
                    $edit_id = $_GET['id'];
                    $stmt = $pdo->prepare("SELECT * FROM bit_bank WHERE id = ?");
                    $stmt->execute([$edit_id]);
                    $edit_item = $stmt->fetch(PDO::FETCH_ASSOC);
                    if ($edit_item) {
                ?>
                        <form method="POST" enctype="multipart/form-data"
                            style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                            <h4>Edit Bit Bank (ID: <?php echo $edit_item['id']; ?>)</h4>
                            <input type="hidden" name="bit_bank_id" value="<?php echo $edit_item['id']; ?>">
                            <input type="hidden" name="existing_file_path"
                                value="<?php echo htmlspecialchars($edit_item['file_path']); ?>">

                            <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                                <div class="form-group">
                                    <label class="form-label">Year</label>
                                    <select name="year" class="form-input" required>
                                        <?php for ($y = 1; $y <= 4; $y++): ?>
                                            <option value="<?php echo $y; ?>" <?php echo ($edit_item['year'] == $y) ? 'selected' : ''; ?>>Year <?php echo $y; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Semester</label>
                                    <select name="semester" class="form-input" required>
                                        <?php for ($s = 1; $s <= 8; $s++): ?>
                                            <option value="<?php echo $s; ?>" <?php echo ($edit_item['semester'] == $s) ? 'selected' : ''; ?>>Semester <?php echo $s; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Subject</label>
                                    <input type="text" name="subject" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_item['subject']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Bit Bank File (PDF)</label>
                                    <?php if (!empty($edit_item['file_path'])): ?>
                                        <a href="<?php echo htmlspecialchars($edit_item['file_path']); ?>" target="_blank">Current
                                            File</a><br>
                                    <?php endif; ?>
                                    <input type="file" name="bit_bank_file" class="form-input" accept=".pdf">
                                </div>
                            </div>
                            <button type="submit" name="update_bit_bank" class="btn">Update Bit Bank</button>
                            <a href="admin_dashboard.php#manage-bit-bank" class="btn"
                                style="background:#ccc; color:#333;">Cancel</a>
                        </form>
                <?php
                    }
                }
                ?>
            </div>

            <!-- Manage Question Bank Section -->
            <div id="manage-question-bank" class="content-subsection">
                <h3>Manage Question Bank</h3>

                <form method="POST" enctype="multipart/form-data" style="margin-bottom: 2rem;">
                    <h4>Add New Question Bank</h4>

                    <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                        <div class="form-group">
                            <label class="form-label">Year</label>
                            <select name="year" class="form-input" required>
                                <option value="1">Year 1</option>
                                <option value="2">Year 2</option>
                                <option value="3">Year 3</option>
                                <option value="4">Year 4</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Semester</label>
                            <select name="semester" class="form-input" required>
                                <option value="1">Semester 1</option>
                                <option value="2">Semester 2</option>
                                <option value="3">Semester 3</option>
                                <option value="4">Semester 4</option>
                                <option value="5">Semester 5</option>
                                <option value="6">Semester 6</option>
                                <option value="7">Semester 7</option>
                                <option value="8">Semester 8</option>
                            </select>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Subject</label>
                            <input type="text" name="subject" class="form-input" required>
                        </div>

                        <div class="form-group">
                            <label class="form-label">Question File (PDF)</label>
                            <input type="file" name="question_file" class="form-input" accept=".pdf,.doc,.docx,.docm,.odt">
                        </div>
                    </div>

                    <button type="submit" name="add_question_bank" class="btn">Add Question Bank</button>
                </form>

                <h4>Existing Question Bank</h4>
                <div class="existing-table-wrapper">
                    <table>
                        <thead>
                            <tr>
                                <th>ID</th>
                                <th>Year</th>
                                <th>Semester</th>
                                <th>Subject</th>
                                <th>Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            <?php
                            $stmt = $pdo->query("SELECT * FROM question_bank ORDER BY year, semester, subject");
                            $question_bank = $stmt->fetchAll(PDO::FETCH_ASSOC);
                            foreach ($question_bank as $item) {
                                echo '<tr>';
                                echo '<td>' . $item['id'] . '</td>';
                                echo '<td>' . $item['year'] . '</td>';
                                echo '<td>' . $item['semester'] . '</td>';
                                echo '<td>' . $item['subject'] . '</td>';
                                echo '<td>';
                                echo '<a href="admin_dashboard.php?edit=true&type=question_bank&id=' . $item['id'] . '#manage-question-bank" class="btn" style="padding: 0.3rem 0.5rem; background: #36a2eb; margin-right:0.3rem;">Edit</a>';
                                echo '<a href="admin_dashboard.php?delete=true&type=question_bank&id=' . $item['id'] . '" class="btn" style="padding: 0.3rem 0.5rem; background: #ff6384;" onclick="return confirm(\'Are you sure you want to delete this question bank?\')">Delete</a>';
                                echo '</td>';
                                echo '</tr>';
                            }
                            ?>
                        </tbody>
                    </table>
                </div>
                <?php
                // Show edit form if editing question bank
                if (isset($_GET['edit']) && $_GET['type'] === 'question_bank' && isset($_GET['id'])) {
                    $edit_id = $_GET['id'];
                    $stmt = $pdo->prepare("SELECT * FROM question_bank WHERE id = ?");
                    $stmt->execute([$edit_id]);
                    $edit_item = $stmt->fetch(PDO::FETCH_ASSOC);
                    if ($edit_item) {
                ?>
                        <form method="POST" enctype="multipart/form-data"
                            style="margin-bottom:2rem; background:#f9f9f9; padding:1.5rem; border-radius:8px;">
                            <h4>Edit Question Bank (ID: <?php echo $edit_item['id']; ?>)</h4>
                            <input type="hidden" name="question_bank_id" value="<?php echo $edit_item['id']; ?>">
                            <input type="hidden" name="existing_question_file"
                                value="<?php echo htmlspecialchars($edit_item['question_file']); ?>">

                            <div style="display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1rem;">
                                <div class="form-group">
                                    <label class="form-label">Year</label>
                                    <select name="year" class="form-input" required>
                                        <?php for ($y = 1; $y <= 4; $y++): ?>
                                            <option value="<?php echo $y; ?>" <?php echo ($edit_item['year'] == $y) ? 'selected' : ''; ?>>Year <?php echo $y; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Semester</label>
                                    <select name="semester" class="form-input" required>
                                        <?php for ($s = 1; $s <= 8; $s++): ?>
                                            <option value="<?php echo $s; ?>" <?php echo ($edit_item['semester'] == $s) ? 'selected' : ''; ?>>Semester <?php echo $s; ?></option>
                                        <?php endfor; ?>
                                    </select>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Subject</label>
                                    <input type="text" name="subject" class="form-input"
                                        value="<?php echo htmlspecialchars($edit_item['subject']); ?>" required>
                                </div>
                                <div class="form-group">
                                    <label class="form-label">Question File (PDF)</label>
                                    <?php if (!empty($edit_item['question_file'])): ?>
                                        <a href="<?php echo htmlspecialchars($edit_item['question_file']); ?>"
                                            target="_blank">Current File</a><br>
                                    <?php endif; ?>
                                    <input type="file" name="question_file" class="form-input" accept=".pdf">
                                </div>
                            </div>
                            <button type="submit" name="update_question_bank" class="btn">Update Question Bank</button>
                            <a href="admin_dashboard.php#manage-question-bank" class="btn"
                                style="background:#ccc; color:#333;">Cancel</a>
                        </form>
                <?php
                    }
                }
                ?>
            </div>

            <!-- Change User Password Section -->
            <div id="change-password" class="content-subsection full-page-section">
                <h3 class="section-title">Change User Password</h3>
                <form id="changePasswordForm" class="password-form">
                    <div class="form-grid">
                        <div class="form-group">
                            <label class="form-label">User Roll Number</label>
                            <input type="text" name="user_roll_number" id="user_roll_number" class="form-input"
                                required>
                        </div>
                        <div class="form-group">
                            <label class="form-label">New Password</label>
                            <input type="password" name="new_password" id="new_password" class="form-input" required>
                        </div>
                        <div class="form-group">
                            <label class="form-label">Confirm Password</label>
                            <input type="password" name="confirm_password" id="confirm_password" class="form-input"
                                required>
                        </div>
                        <div class="form-group otp-group">
                            <label class="form-label">Enter OTP</label>
                            <div class="otp-input-container">
                                <input type="text" name="otp" id="otp" class="form-input" required>
                                <button type="button" id="sendOtpBtn" class="btn otp-btn">Send OTP</button>
                            </div>
                        </div>
                    </div>
                    <button type="button" id="changePasswordBtn" class="btn submit-btn">Change Password</button>
                </form>
                <div id="passwordAlert" class="alert-container"></div>
            </div>
        </section>
    </div>
</div>

<!-- Up Arrow Button -->
<button id="scrollToTopBtn" title="Go to top" style="
    position: fixed;
    bottom: 32px;
    right: 32px;
    z-index: 3000;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    border: none;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    box-shadow: 0 2px 8px #667eea44;
    cursor: pointer;
    font-size: 1.6rem;
    display: none;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
">
    <i class="fas fa-arrow-up"></i>
</button>
<script>
    // Show/hide button on scroll
    const scrollBtn = document.getElementById('scrollToTopBtn');
    window.addEventListener('scroll', function() {
        if (window.scrollY > 200) {
            scrollBtn.style.display = 'flex';
        } else {
            scrollBtn.style.display = 'none';
        }
    });
    // Scroll to top on click
    scrollBtn.addEventListener('click', function() {
        window.scrollTo({
            top: 0,
            behavior: 'smooth'
        });
    });
</script>

<?php include 'includes/footer.php'; ?>