Noticed that iOS 13 mail in Dark Mode changes the color scheme of a lot of e-mails. In my codebase, all the colors are affected which completely breaks the intended design. I noticed e-mails where this doesn't happen, however, I don't see anything special that disables this behavior.

I tried several things:

Inline background-colors, bgcolor, background-color in a class etc. Nothing seems to disable this annoying behavior.

Any ideas?