The :has Relational Pseudo-Class

Oxygen XML Editor supports the CSS Level 4 subject selector (currently a working draft at W3C http://www.w3.org/TR/selectors4/), as described in the Subject Selector topic. Oxygen XML Editor also supports the :has relational pseudo-class that has similar functionality and it can match an element by taking its child elements into account. For more information, see https://drafts.csswg.org/selectors-4/#relational.

You can create conditions that take into account the structure of the matching element.

For example:

table:has( tbody > thead){
 border: 1px solid red;
}

This will result in a border being drawn for the table elements that contain at least a thead element in the tbody element.

Important: The current implementation has a known limitation. The general descendant selectors are taken into account as direct child selectors. For example, the following two CSS selectors are considered equivalent:

:has(b c)

and

:has(> b > c)