QR code component with relative width

Thanks for checking this out

• This is my third challenge. Implemented with pure html css.
• It's a pretty simple challenge, however, I've learnt how to make a beautiful QR code component.
• I just learnt about relative units (rem and em) lately, and implemented in this challenge.
• I make the font and card width to be relative even with the browser font size. (if you adjust the browser font size, the card will become smaller or larger)

"If you have any suggestions or feedback for my code, please feel free to comment." I would greatly appreciate all feedback.