Semantic HTML, responsive mobile first design, media query , Flex-grid

I would suggest the following changes:

1. Increase the font size of the QR component title. A neat little trick that I use is to set font-size: 10px at html root in your CSS file i.e. html {font-size: 10px). Then you can comfortably use rem units in your size calculations. 2)Reduce the margin between the QR picture and the heading!