Best practices for embedded code and Safari's Reader View

Hello everyone,

I’ve just received audience feedback and my page looks awful on Safari’s Reader View.
Can anyone share best practices regarding embedded code snippets?

For context: https://www.davidseek.com/ood

Originally I went with GitHub Gists with custom styling.
Looks great on Mac, but turns into something like this Mobile Reader View:

Screen Shot 2021-02-08 at 2.54.20 PM

Now when using the Markup version and styling it custom, it also looks great,
but the Reader View version is even worse. Much worse.

With Code comments gone there’s not even value in my post anymore.
Help is very appreciated.

PS: This is the desire and current styling without Reader View.