[uallo]

What do you mean by "official documentation"? The specification [1]? MDN [2]?

[1] https://drafts.csswg.org/

[2] https://developer.mozilla.org/en-US/docs/Web/CSS

The former is not meant as a learning resource for new web devs. And the latter (which is neither official nor authoritative) usually has information about the "baseline" support and browser compatibility tables.

[lesser_value]

The former, I'm not really new just looking to increase my understanding of some concepts and learning from that has not been too fun. I don't think MDN goes in depth as much as I'd like it to.