Support more PyData theme colors for badges

[user27182]

Context

I have found that the existing dark and light colors have low-contrast when viewing a site with the dark and light themes applied, respectively, and are therefore hard to see/read. E.g. see this badge :

from pyvista/pyvista#6475.

I went looking for an alternative, but found that dark and light are the only grayscale options with outlines supported by Sphinx Design: https://sphinx-design.readthedocs.io/en/latest/badges_buttons.html

Proposal

Additional colors are available from the PyData theme:
https://pydata-sphinx-theme.readthedocs.io/en/stable/user_guide/styling.html#color-variables

Something like the surface and on-surface colors might be good alternatives since these change with the theme.

Perhaps all the other PyData theme colors could be supported as well.

Tasks and updates

No response

[user27182]

Looks like there are three undocumented colors: muted, black, and white

sphinx-design/sphinx_design/shared.py

Lines 19 to 31 in 0b178a9

	SEMANTIC_COLORS = (
	"primary",
	"secondary",
	"success",
	"info",
	"warning",
	"danger",
	"light",
	"muted",
	"dark",
	"white",
	"black",
	)

Here's what all the colors look like (including undocumented ones) with the light and dark PyData theme applied:

Based on this it looks like muted produces the best results for what I'm looking for, as the outline version is clearly visible with either the dark or light theme.

So, at the very least, this issue is a documentation issue. It would be good to update the docs to include the three undocumented colors muted, black, and white.