chromium/third_party/blink/web_tests/external/wpt/css/css-scrollbars/scrollbar-color-scheme-dynamic-4-ref.html

<!doctype html>
<style>
  :root {
    color-scheme: light;
  }
  body {
    display: flex;
    flex-wrap: wrap;
    overflow: scroll;
  }
  .container {
    color-scheme: dark;
    scrollbar-gutter: stable;
    overflow: scroll;
    flex: 0 0;
    height: 200px;
    min-width: 200px;
    margin: 1px;
    padding: 0px;
    border: none;
    background: deepskyblue;
  }
</style>
<div class="container"></div>