chromium/third_party/blink/web_tests/external/wpt/css/CSS2/normal-flow/negative-margin-001.html

<!DOCTYPE html>
<title>Negative margins in LTR/RTL and BFC/non-BFC</title>
<link rel="author" title="Koji Ishii" href="[email protected]">
<link rel="help" href="https://www.w3.org/TR/CSS22/box.html#margin-properties" title="Margin properties">
<link rel="match" href="negative-margin-001-ref.html">
<style>
html, body {
  margin: 0;
}
html {
  margin-left: 10px;
}
outer {
  display: block;
  border: blue 10px solid;
  width: 100px;
}
inner {
  display: block;
  border: orange 10px solid;
  margin-left: -20px;
  margin-right: -50px;
  height: 10px;
}
inner.bfc {
  overflow: hidden;
}
</style>
<body>
  <outer>
    <inner></inner>
  </outer>
  <outer dir="rtl">
    <inner></inner>
  </outer>
  <outer>
    <inner class="bfc"></inner>
  </outer>
  <outer dir="rtl">
    <inner class="bfc"></inner>
  </outer>
</body>