Description
Rough proposal: a pseudo-class, such as p:within(a) selects p elements which have an a element anywhere in their ancestor tree.
E.g. it would select any of the <p> elements here:
<div>
<a href="http://example.org/">
<p>I match
</a>
</div>
<a href="http://example.org/">
<div>
<p>I match
</div>
</a>But not this one:
<div>
<p>I don’t match, <a href="http://example.org/">me neither</a>
</div>While writing my first major design using CSS Nesting, this seemed like a missing feature, mainly for maintainability but also because truly accounting for all possible nesting situations to target the element wanted using regular selectors could be tricky within a complex nesting of selectors. A strong use case in particular (as implied above) is when elements might sometimes be inside links and sometimes not. This would allow them to be styled or restyled in a way more clearly indicating that they can be interacted with as links.
Link to spec: https://www.w3.org/TR/selectors-4/