Responsive and functional product list with cart

What are you most proud of, and what would you do differently next time?

Overview

I created a simple webpage with HTML, CSS and JavaScript. Next time I would like to do these tasks with a framework like Angular or a library like React.

What challenges did you encounter, and how did you overcome them?

It was difficult to perform all the functionality with VanillaJs, especially while I had to update values that had to be displayed in DOM.