Thanks for the feedback. The colors are more syntax highlighting (vs indicating anything important), I'd like to research best practices here. I wonder if there's any client-side settings I can detect to indicate a different stylesheet should load.

blue is a good option instead of green. same reason some places in the world have blue, rather than green signals for traffic lights afaik :)

How would you work around this? Do browsers have a colorblind mode/header/whatever? Or should we just never use red/green combination?

I'm sure you mean - those are two different colours. If not, oh boy do I have news for you.