Responsive page using flexbox

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

Even though it's something so basic, I'm happy to be able to complete it, even though it might not be how a true professional would develop the website, but with few conditions I'm evolving.

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

where it took me the longest to complete was to center the qr-code image with the container, but little by little I racked my brains and looked at my notes until I discovered a method

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

Just to know if the algorithm is right and where I could improve.