hiba-dotcom/task-manager — reverse-engineered prompt

Build me a simple task manager web app from this project. I want a clean page where I can add tasks, see them in a list, mark them as done, edit the text, and delete tasks I no longer need. Keep it easy to use, with a clear input box, an add button, and separate visual styles for pending and completed tasks.

Please make it work with the existing project setup and files, especially the current app.js and public folder if that is how it is structured. Since there is no README, keep the scope simple and practical. The app should run locally with npm, load in the browser without errors, and remember tasks after refreshing if that fits the current setup. Make the design neat and responsive so it looks okay on a phone and a laptop.

If anything is missing, make reasonable choices and update the project so I can run it easily.