Is there some sort of reddit CSS guide?

Hello everyone,,
I learned CSS when I was younger on Neopets and remember most of it, but I don't quite know what reddit calls everything/how attributes are named. Is there some sort of guide floating around the interwebz or is it going to be a trial and error thing for me?
https://reversephonelookup.onl/ https://curated.onl/nba-reddit/ https://pcbuilder.onl/pcpartpicker/