Split Screen Opposite Direction Looping Scroll

Hello,

I'm trying to create a split screen scrolling effect where everything on the page is contained to the size of the screen (100% height?) This website I'm trying to replicate uses flexbox: https://codeastudio.com/

This is a forum I found where they lay out some issues: https://stackoverflow.com/questions/70323333/split-column-50-each-scrolling-in-the-opposite-direction-continuous-loop and I've noticed Codea has some glitches too but I'd still like to figure it out. 

If they just independently scrolled at a height of 100%, that would be fine too. I found this forum but am not sure how/where to implement the code: https://stackoverflow.com/questions/51263115/split-screen-containers-with-scrolling

It's for the CODEA and STUDIO pages of my replica site. https://violet-conch-62zc.squarespace.com/ password is brineintopedro.

Thanks, any help would be appreciated.