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Test Info: Warnings

<!DOCTYPE html>
<title>Tests CSS transition of anchor() across tree scopes</title>
<link rel="help" href="https://github.com/w3c/csswg-drafts/issues/8180"></script>
<link rel="author" href="mailto:xiaochengh@chromium.org">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
body {
margin: 0;
}
#anchor1 {
width: 100px;
height: 100px;
background: orange;
anchor-name: --a;
}
#anchor2 {
width: 100px;
height: 100px;
margin-top: 200px;
margin-left: 300px;
background: orange;
}
#anchor2.after::part(target) {
top: anchor(--a top);
left: anchor(--a right);
}
</style>
<div id="anchor1"></div>
<div id="anchor2"></div>
<script>
setup(() => {
let shadow = anchor2.attachShadow({mode: 'open'});
shadow.innerHTML = `
<style>
:host { anchor-name: --a; }
#target {
position: fixed;
width: 100px;
height: 100px;
background: lime;
top: anchor(--a top);
left: anchor(--a right);
transition: all 10s -5s linear;
}
</style>
<div id="target" part="target"></div>
`;
});
test(() => {
let target = anchor2.shadowRoot.getElementById('target');
// Forces layout
target.offsetLeft;
// Triggers a transition from using #anchor2 to using #anchor1,
// starting immediately at 50% progress.
anchor2.classList.add('after');
assert_equals(target.offsetLeft, 250);
assert_equals(target.offsetTop, 150);
}, 'Transition with anchor names defined in different tree scopes');
</script>