QR code with HTML and CSS

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

I'm proud of my ability to replicate the given design as close as possible to it.

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

I had trouble getting curved edges with border-radius while having padding. To solve this I referred to stack overflow, in which a user suggested to add the padding value to the border-radius value to solve it

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

What do you guys think of my approach to center the QR image in the div element, and how differently would you have done it?