Responsive page using basic HTML & CSS

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

Just keep learning and improving.

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

Challenge: To center the QR card vertically. At first, I put the QR card in a div and make that div a flexbox, but seems like it didn't work. (Edit) Finally it works!

Solution 1: By manually calculate the margin-top property based on the different height of the screen (812px and 960px)

(Edit) Solution: Make the position property of QR code container into absolute, set the top & left to 50%, and transform it so that it moves to the center

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

How to vertically center div element in body element. (Edit) Had the solution for previous problem.