QR code First Challenge using basic HTML & CSS with flexbox

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

Most significant accomplishment was probably just using flexbox for the first time; nothing else too significant in this solution.

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

figuring out how to center elements both vertically and horizontally, as well as centering elements at the bottom of the page, which were both solved through the use of flexbox.

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

Mostly formatting: does the way I formatted my code make sense, and how can can I improve it for the future? Also, any fixes in terms of my text formatting (I know it's slightly off).