<!DOCTYPE html>
<html>
<head>
<link rel="help" href="https://drafts.csswg.org/css-env-1/">
<title>Test unknown env() names will override previous values</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
</head>
<body style="background-color: green; background-color: env(unknown);">
<script>
test(() => {
const style = window.getComputedStyle(document.body);
assert_equals(style.getPropertyValue("background-color"), "rgba(0, 0, 0, 0)");
});
</script>
</body>
</html>