<!DOCTYPE html>
<title>CSS Anchor Positioning: Pseudo elements as anchors</title>
<link rel="help" href="https://drafts.csswg.org/css-anchor-1/#position-anchor">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
.cb {
position: relative;
width: 200px;
height: 200px;
}
#anchor1.enabled::before {
display: block;
width: 100px;
height: 100px;
content: "";
anchor-name: --a1;
background: blue;
}
#anchor2.enabled::after {
display: block;
width: 100px;
height: 100px;
content: "";
anchor-name: --a2;
background: pink;
}
.anchored {
position: absolute;
width: 100px;
height: 100px;
left: anchor(right);
top: anchor(bottom);
background: orange;
}
#anchored1 { position-anchor: --a1; }
#anchored2 { position-anchor: --a2; }
</style>
<div class="cb">
<div id="anchor1"></div>
<div id="anchored1" class="anchored"></div>
</div>
<div class="cb">
<div id="anchor2"></div>
<div id="anchored2" class="anchored"></div>
</div>
<script>
test(() => {
assert_equals(anchored1.offsetLeft, 0);
assert_equals(anchored1.offsetTop, 0);
anchor1.className = "enabled";
assert_equals(anchored1.offsetLeft, 100);
assert_equals(anchored1.offsetTop, 100);
}, "::before as anchor dynamically generated");
test(() => {
assert_equals(anchored2.offsetLeft, 0);
assert_equals(anchored2.offsetTop, 0);
anchor2.className = "enabled";
assert_equals(anchored2.offsetLeft, 100);
assert_equals(anchored2.offsetTop, 100);
}, "::after as anchor dynamically generated");
</script>
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