script.js

// Navbar scroll effect
const navbar = document.getElementById('navbar');
window.addEventListener('scroll', () => {
  navbar.classList.toggle('scrolled', window.scrollY > 20);
});

// Mobile nav toggle
const navToggle = document.getElementById('navToggle');
const navLinks = document.getElementById('navLinks');
navToggle.addEventListener('click', () => {
  navLinks.classList.toggle('open');
  navToggle.classList.toggle('active');
});

// Close mobile nav on link click
navLinks.querySelectorAll('a').forEach(link => {
  link.addEventListener('click', () => {
    navLinks.classList.remove('open');
    navToggle.classList.remove('active');
  });
});

// Active nav link on scroll
const sections = document.querySelectorAll('section[id]');
function updateActiveLink() {
  const scrollY = window.scrollY + 100;
  sections.forEach(section => {
    const top = section.offsetTop;
    const height = section.offsetHeight;
    const id = section.getAttribute('id');
    const link = document.querySelector(`.nav-links a[href="#${id}"]`);
    if (link) {
      link.classList.toggle('active', scrollY >= top && scrollY < top + height);
    }
  });
}
window.addEventListener('scroll', updateActiveLink);

// Fade-in on scroll (Intersection Observer)
const fadeEls = document.querySelectorAll('.section-title, .card, .pub-item, .skill-category, .timeline-item, .highlight-card, .contact-item, .about-text');
const observer = new IntersectionObserver((entries) => {
  entries.forEach(entry => {
    if (entry.isIntersecting) {
      entry.target.classList.add('visible');
      observer.unobserve(entry.target);
    }
  });
}, { threshold: 0.15 });

fadeEls.forEach(el => {
  el.classList.add('fade-in');
  observer.observe(el);
});