Responsive accessible FAQ accordion using HTML/CSS/JS

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

As my first project using JavaScript, I think I managed to make a very DRY code. I'll try to make some reusable and pre-rendering HTML next time.

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

My main challenge was to not repeat myself (stay DRY) when coding.

What specific areas of your project would you like help with?

The JS, mainly.