saranyapo/PrepAI-MERN ? reverse-engineered prompt

Build me a full stack mock interview prep app for students and aspiring developers.

I want users to be able to sign up, log in, and take timed mock interviews across a few tracks like MERN, Java, Python, and HR. After each session, the app should give a clear score, helpful AI feedback, benchmark answers, and a breakdown of what they did well and what they missed. Students should also be able to look back at past interviews, track their progress, and save personal prep notes like cheat sheets, code snippets, and behavioral story ideas.

I also need an admin area where I can manage users, interview categories, questions, and see basic platform stats. Please make the UI modern, clean, and responsive, with a polished dark style. Use a MongoDB backed Node and React setup, add authentication and role based access, and if the AI service is not configured, fall back to sensible built in grading so the app still works.