Ashwanthkk/CBT ? reverse-engineered prompt

Build me a full online CBT exam system that works end to end.

I want students to be able to log in, see their assigned test, start a timed exam, move through questions, mark answers, review before submitting, and get a clear result screen at the end. It should handle basic things like autosaving progress, preventing multiple submissions, and showing remaining time while the test is running.

I also need a simple admin side where I can create exams, add questions and options, set the timer, and view submitted results. Make the interface clean and easy to use on both desktop and laptop screens.

Use the existing backend and frontend structure in the repo, and keep the backend solid and understandable. If you need current docs or best practices for anything, look them up online before implementing.