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                <h1>CSS Nesting Feature Detection</h1>

<p id="output">Does your browser support <a href="" target="_top">CSS Nesting</a>?</p>

<p class="has-support has-nesting">✅ Your browser supports CSS nesting</p>
<p class="no-support no-nesting">❌ Your browser does not support CSS nesting</p>

	<p>More ways of testing</p>
		<li><a href="" target="_top" class="active">Method 1a – Nesting affecting classes</a></li>
		<li><a href="" target="_top">Method 1b – Nesting driving a Space Toggle</a></li>
		<li><a href="" target="_top">Method 2 – <code>@supports</code>, with a caveat</a></li>


                .has-nesting {
	display: none;
html {
	& .has-nesting {
		display: block;
	& .no-nesting {
		display: none;

.has-support {
	background-color: #ff00002b;

	margin: 1em 0;
	padding: 1em;
	border: 1px solid #ccc;

.has-support {
	background-color: #00ff002b;

pre {
	border: 1px solid #dedede;
	padding: 1em;
	background: #f7f7f7;
	font-family: "Courier 10 Pitch", Courier, monospace;
	overflow-x: auto;

aside {
	margin-top: 10rem;
	border-top: 1px solid #333;
	padding: 0.5em 0;
	opacity: 0.7;

aside > :first-child {
	margin-top: 0;
aside > :last-child {
	margin-bottom: 0;

aside .active {
	font-weight: bold;

html {
	max-width: 76ch;
	padding: 3rem 2rem;
	margin: auto;
	line-height: 1.5;
	font-size: 1.25rem;
body {
	margin: 0;
	padding: 0;
a:visited {
	color: blue;