vidushisingh3082-source/E_Kart_with_pay ? reverse-engineered prompt

Build me a full stack shopping site called MERN Shop that feels modern and works well on phone and desktop.

I want customers to be able to sign up and log in, browse products, view product details, add items to a cart, and place orders at checkout. The checkout should support Razorpay payments as well as cash on delivery, and orders should be confirmed properly after payment. Please include a clean admin area too, where I can manage products, banners or featured items, and see orders. New users should start as normal customers, and I can turn one into an admin from the database when needed.

Use a React frontend with a simple responsive design, and a Node, Express, MongoDB backend for the API. If you need to look up current docs online for anything, go ahead. Make sure the app runs locally with clear setup, basic auth protection, and image uploads working if Cloudinary details are added.