How can I have all these elements centered?

Question

https://code.sololearn.com/WPIJ0G4KLgFf/?ref=app

I tried to put them into a <div align="center"> or <article align="center"> tag, but it looks like they are not affected by it as I've already specified their position in CSS, but I'd like that the percentual position that I've specified was relative to one of these block tags, not to the html file.
CAN YOU SEND ME THE MODIFIED CODE, PLEASE?

Answer 1

margin:auto;

Answer 2

Can you send me the modified code?