Fix: Fixed color conversion helpers

[lukeblevins]

Resolved / Related Issues

• Were these changes approved in an issue or discussion with the project maintainers? In order to prevent extra work, feature requests and changes to the codebase must be approved before the pull request will be reviewed. This prevents extra work for the contributors and maintainers.
  Closes Bug: Default color schemes have very little impact in the color scheme #11989

Validation
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  1. Open app ...
  2. Click settings button ...

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[lukeblevins]

@yaira2 fyi

[ferrariofilippo]

LGTM and works for me

Light B/A:

Dark B/A: