Improve accessibility of default palette

[danielchalmers]

Feature request type

Other

Component name

No response

Is your feature request related to a problem?

If you run it through an accessibility checker, you will find MudBlazor fails to meet the minimum contrast levels in several areas.

Describe the solution you'd like

The default palettes should be revised to improve contrast and colors for colorblind users.

Have you seen this feature anywhere else?

No response

Describe alternatives you've considered

No response

Pull Request

• I would like to do a Pull Request

Code of Conduct

• I agree to follow this project's Code of Conduct

[danielchalmers]

cc @jperson2000 moved here from #8987

[danielchalmers]

Switch - #8988 (comment)

Material 2:

[danielchalmers]

Default button uses hover effect at all times with poor text contrast - #8521

[igotinfected]

I'm red-green colourblind, feel free to ping me if you need a test subject :) We use our own colour palette at work so I haven't really had to stare at the default one for too long, nothing to add at the moment.

[danielchalmers]

This applies to the docs too. The contrast is poor. Compare to other sites like GitHub, MUI, Twitter, etc etc