riteshpatidar08/mern138 ? reverse-engineered prompt

Build me a simple browser based project from these files that actually works when I open index.html.

I want a clean little page with two small features, one for adding notes and one for adding items to a cart. The notes part should let me type something, save it, show it in a list, and remove items if I want. The cart part should let me click buttons to add items, show the current cart contents, update the total, and let me clear or remove items too.

Please wire the JavaScript together in a straightforward way so it is easy to understand and tweak later. Keep the page simple and responsive, with basic styling so it looks tidy. If anything is missing or unclear, make sensible choices and keep it lightweight. If you need current browser guidance or small helper ideas, look them up online first.