sumitkadam20006/mern-auth-project ? reverse-engineered prompt

Build me a simple full stack web app with a frontend and a backend, focused on user sign up, login, and logout.

I want a clean, modern interface where someone can create an account, sign in, and see a basic protected page after logging in. If they are not signed in, they should be sent back to the login screen. Please include a working backend API for authentication, connect it to the frontend, and make the whole thing feel polished and easy to use.

Keep the setup straightforward so I can run the frontend and backend separately without a lot of extra work. If you need to check current docs or best practices for anything, go ahead and look them up online. Please also add a simple README with how to start the project and what each part does.