📄 Alpha channel modifier related to Color is not documented

[fightingdreamer]

What is the improvement or update you wish to see?

Will be nice to have 2-3 lines describing how to get :rgb(0, 0, 0, 0.6) from :black.

Is there any context that might help us understand?

Format and values range for alpha channel are: /0.0 <> /1.0, eg: :black/0.6.

Wonderful project, I really like design choices — most native CSS rules can be translated 1 to 1, so I don't need to remember every custom class-name ❤️ .

Does the docs page already exist? Please link to it.

No response