[BUG]: Custom 404 Page Missing for Invalid Routes

[anushka11p]

Description of the Bug

When navigating to a non-existent route on the website, the application does not display a proper custom 404 error page. Users are presented with a generic error response or an unclear page, which can lead to confusion and a poor user experience.

Steps to Reproduce

1. Visit the application: https://param20h-pdf-assit-rag.hf.space/
2. Manually enter an invalid URL path, for example:
3. https://param20h-pdf-assit-rag.hf.space/random-page
4. https://param20h-pdf-assit-rag.hf.space/test404
5. press enter and observe

Expected Behavior

A user-friendly custom 404 page should be displayed.
The page should clearly indicate that the requested page does not exist.
Users should be provided with navigation options such as:
Return to Home
Upload PDF
Go Back

Screenshots / Logs

No response

Environment

macOS

GSSoC '26

• Yes, I am participating in GirlScript Summer of Code and would like to fix this.

[github-actions]

Hi @anushka11p! 👋

Thanks for opening this issue! We are thrilled to have you contribute to PDF-Assistant-RAG for GSSoC 2026.

📌 Before you start:

• Make sure you have read our Contributing Guidelines.
• Wait for a project admin to assign this issue to you before working on it.
• Remember to branch off dev and not main.

Happy Coding! 🚀

[anushka11p]

please assign this to me under gssoc'26