CSS · Selectors and cascade

:where()

Like :is() but with zero specificity, so later rules override it without a fight.

cssRunnable example css course

Syntax

:where(h1, h2)

Example

Try it

:where(h1, h2) { margin-block: 0.4em; }

Reference pages are the quick answer. The course explains the why, shows the full example and ends with a challenge.