chromium/third_party/blink/web_tests/external/wpt/css/css-scoping/host-is-004.html

<!doctype html>
<meta charset="utf-8">
<title>:host and :is (combined with something else)</title>
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:[email protected]">
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://drafts.csswg.org/selectors/#featureless">
<link rel="match" href="/css/reference/ref-filled-green-100px-square-only.html">
<p>Test passes if there is a filled green square.</p>
<div id="host"></div>
<script>
  host.attachShadow({mode: "open"}).innerHTML = `
    <style>
      :host {
        width: 100px;
        height: 100px;
        background-color: green;
      }
      :is(:host(#not-host), #host) {
        background-color: red;
      }
    </style>
  `;
</script>