tamanwit/YFeed- ? reverse-engineered prompt

Build me a simple full stack social media app where people can sign up, log in, make posts, see a feed, like posts, comment, and view user profiles.

I want it to feel clean and modern, with a good mobile friendly layout and a smooth experience. Use a typical MERN setup and wire up the frontend and backend so the core features actually work end to end. Include basic auth, post creation, editing and deleting your own posts, and a way to browse other users.

If anything is unclear, make sensible choices and keep it polished. Look up current docs online if you need to, and set it up so I can run and test it easily.