chromium/third_party/blink/web_tests/external/wpt/css/css-anchor-position/position-try-004.html

<!DOCTYPE html>
<title>Tests margin properties in position fallback</title>
<link rel="help" href="https://drafts.csswg.org/css-anchor-position-1/#accepted-try-properties">
<link rel="author" href="mailto:[email protected]">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/check-layout-th.js"></script>
<script src="support/test-common.js"></script>

<style>
body {
  margin: 0;
}

.cb {
  width: 300px;
  height: 150px;
  position: relative;
  background: lightgray;
}

.anchor {
  position: absolute;
  width: 100px;
  height: 100px;
  top: 25px;
  background: orange;
  anchor-name: --a;
}

.target {
  position: absolute;
  width: 100px;
  height: 100px;
  background: lime;
  position-try-fallbacks: --fallback;
  top: anchor(--a top);
  right: anchor(--a left);
  margin-top: 10px;
  margin-right: 10px;
}

@position-try --fallback {
  inset: auto;
  bottom: anchor(--a bottom);
  left: anchor(--a right);
  margin: 0;
  margin-bottom: 10px;
  margin-left: 10px;
}
</style>

<body onload="checkLayoutForAnchorPos('.target')">

<div class=cb>
  <div class=anchor style="left: 110px"></div>
  <!-- Chooses base style. -->
  <div class=target data-offset-x=0
       data-expected-margin-left=0 data-expected-margin-right=10
       data-expected-margin-top=10 data-expected-margin-bottom=0></div>
</div>

<div class=cb>
  <div class=anchor style="right: 110px"></div>
  <!-- Chooses @position-try block. -->
  <div class=target data-offset-x=200
       data-expected-margin-left=10 data-expected-margin-right=0
       data-expected-margin-top=0 data-expected-margin-bottom=10></div>
</div>

</body>