Launch VS Code Quick Open (⌘+P), paste the following command, and press enter.
ext install flatlanddark
Or install this theme from the extension panel (search for "github theme").
You can find this theme in the Visual Studio Code Marketplace.

This theme has been optimized for JavaScript CSS, SASS(SCSS) and HTML. Other languages are not tested and may differ from the github code styles. Please file an issue or submit a PR in this case.

If you find any issues, bugs, missing stylings or feedback please feel free to file an issue.