nested-size-style-container-invalidation.html

<!DOCTYPE html>
<title>Nested size/style @container-dependent elements respond to container size changes</title>
<link rel="help" href="https://drafts.csswg.org/css-conditional-5/#size-container">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="support/cq-testcommon.js"></script>
<style>
  #container {
    container-type: size;
    width: 1000px;
  }
  #container.narrow {
    width: 600px;
  }
  #target {
    color: red;
  }
  @container (width < 800px) {
    @container style(--foo: bar) {
      #target { color: green; }
    }
  }
</style>
<div id="container">
  <div style="--foo: bar">
    <div id="target">Green?</div>
  </div>
</div>
<script>
  setup(() => assert_implements_container_queries());

  test(() => {
    assert_equals(getComputedStyle(target).color, "rgb(255, 0, 0)");
  }, "Initially red");

  test(() => {
    container.className = "narrow";
    assert_equals(getComputedStyle(target).color, "rgb(0, 128, 0)");
  }, "Green after reducing width");
</script>

chromium/third_party/blink/web_tests/external/wpt/css/css-conditional/container-queries/nested-size-style-container-invalidation.html