KSS is alive? or how to document CSS (and not only)?

Question

css

A couple of years ago, in a CSS book, I read about "knyle style sheets", which they say is a thing that will help with CSS documentation.

The question is, is it used in practice?
What has been replaced?
What would you advise about documenting in the front?

Answer 1

KSS is alive?

KSS is not.
CSS yes.