Thank you. It helped fixing the issue.
One page is https://oradbdev.mathiasmagnusson.com/2020/05/15/scripting-the-oracle-wallet-truststore/. Where the gists are towards the bottom.
Are there ways or well established css for changing the syntax colors to work on dark backgrounds? Or definitions on all the classes github may use in a gist?
I think I see. It is github providing it as part of the embedded gist. But how to override it in the way coblocks sets up the gist?