Codeblocks in Dark Mode

[JetFlightGit]

I am tryining to change to darkmode. Using Stackedit.io online in the browser.
When changing to dark theme through custom settings it does work but tryining to style it correctly so code blocks are highlighted does not work. I tried work arounds such as:
`# Custom CSS for code blocks
css:

• |
  code {
  background-color: #f9f9f929;
  }`

Does not work sadly. Could someone help me with that?

P.S. In darkmode the sidebars and the Project Folder are still light and not dark