nt③">&lt;dashed-ident></a>, and an
element can expose multiple states. Authors can use
<a data-link-type="dfn" href="#custom-state-pseudo-class" id="ref-for-custom-state-pseudo-class⑤">custom state pseudo class</a> with logical <a data-link-type="dfn" href="https://www.w3.org/TR/CSS21/selector.html#x23" id="ref-for-x23">pseudo-classes</a> like
<span class="css">x-foo:is(:--state1, :--state2)</span>, <span class="css">x-foo:not(:--state2)</span>, and
<span class="css">x-foo:--state1:--state2</span>.
</di