<!DOCTYPE html>
<title>Tests CSS animation of anchor(), dynamic anchor-name changes</title>
<link rel="help" href="https://drafts.csswg.org/css-anchor-position-1/">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
  #cb {
    border: 1px solid black;
    width: 400px;
    height: 400px;
    position: relative;
  }
  #a1, #a2 {
    width: 100px;
    height: 100px;
  }
  #a1 {
    background: tomato;
  }
  #a2 {
    background: seagreen;
  }
  .