focus-within-002.html
<!DOCTYPE html>
<html lang=en class="reftest-wait">
<meta charset="utf-8">
<title>Selectors Level 4: focus-within</title>
<link rel="author" title="Keyong Li" href="mailto:kli79@bloomberg.net">
<link rel="author" title="Florian Rivoal" href="mailto:florian@rivoal.net">
<link rel="help" href="https://drafts.csswg.org/selectors-4/#focus-within-pseudo">
<link rel="match" href="focus-within-001-ref.html">
<meta name="assert" content="Test that :focus-within applies to the parent of an element with tabindex where :focus applies.">
<style>
/* Suppress things that cannot be reproduced in the reference file */
:focus {
outline: none;
}
/* Use blue to indicate that the user needs to pay attention.
This element needs to be focused for the test to make sense. */
#focusme:not(:focus) {
border: solid 15px blue;
}
#target:focus-within {
border: solid 15px green;
}
</style>
<p>Test passes if, when the element below is focused,
it is surrounded by a thick green border.
There must be no red or blue once it is focused.</p>
<div id="target">
<div id="focusme" tabindex="1">Focus this element</div>
</div>
<script>
var focusme = document.getElementById('focusme');
focusme.focus();
document.documentElement.classList.remove('reftest-wait');
</script>
</html>