contain-layout-independent-formatting-context-003.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Containment Test: Layout containment independent formatting context</title>
<link rel="author" title="Manuel Rego Casasnovas" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/css-contain-1/#containment-layout">
<link rel="match" href="reference/contain-paint-independent-formatting-context-003-ref.html">
<meta name=assert content="Layout containment elements establish an independent formatting context. The test checks that this feature of paint containment does not appliy to inline elements.">
<style>
.wrapper {
  border: solid thick;
  margin: 1em;
}
</style>
<p>Test passes if it has the same output than the reference.</p>
<div class="wrapper">
  <span style="margin: 1em 0; contain: layout;">
    <div style="margin: 1em 0;">This text should have 1em top and bottom margins.</div>
  </span>
</div>

chromium/third_party/blink/web_tests/external/wpt/css/css-contain/contain-layout-independent-formatting-context-003.html