I think part of the problem was that selectors that looked inwards or outwards from an element was deemed too expensive to parse. It only looked at the current

I think part of the problem was that selectors that looked inwards or outwards from an element was deemed too expensive to parse. It only looked at the current element or following adjacent ones (with + or ~). Now that it's deemed doable without noticeably hurting performance, :has/:not(:has()) basically comes around and allows you the inward/outward selector lookups, e.g. (`.container:has(input:checked) { border: 1px solid green }` ). That said, I do agree it would've been nice if they had the foresight to use `:has(:checked)` (or some kind of :if() syntax), but it's all hindsight 20/20 and it was the wild west on the web back when a lot of these features were spec'd/implemented. Kinda wish there was a new css version every 10 years or so to fix the inconsistencies (which you would have to opt into).