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	<h1>How to Create a Blurry Header with CSS Backdrop Filter</h1>
	<code><pre>.blurry-header {
	position: sticky;
	top: 0;
	background-color: rgba(255, 255, 255, 0.7);
	backdrop-filter: blur(10px);
	<div class="u-position-relative">
		<div class="blurry-header">
			<p>Scroll down and see how this sticky header blurs the content behind it.</p>
			<!-- Wait, whaaaat??? How long has this been a thing? -->

		<div class="u-full-width">
			<img src='' alt=''>
  <h2>Browser Support <small>(as of 2019-11-11)</small></h2>
    <dt>IE</dt><dd>⚠️ Fallback</dd>
    <dt>Edge</dt><dd>✅ 17+</dd>
    <dt>Firefox</dt><dd>⚠️ Fallback <i>but…</i> under consideration / behind a feature flag in 70+</dd>
    <dt>Chrome</dt><dd>✅ 76+</dd>
    <dt>Safari</dt><dd>✅ 9+</dd>
    <dt>Opera</dt><dd>✅ 64+</dd>
    <dt>iOS Safari</dt><dd>✅ 9+</dd>
    <dt>Opera Mini</dt><dd>⚠️ Fallback</dd>
    <dt>Android Browser</dt><dd>✅ 76+</dd>
    <dt>Chrome for Android</dt><dd>✅ 78+</dd>
		<li><a href="" target="_blank" rel="noopener">Can I use… CSS Backdrop Filter</a></li>
		<li><a href="" target="_blank" rel="noopener">MDN: backdrop-filter</a></li>



                html {
	box-sizing: border-box;

::before {
	box-sizing: inherit;

body {
	margin: 1rem auto 30rem;
	line-height: 1.4;
	tab-size: 4;

main {
	display: block; /* Fix IE rendering main as inline */
	margin: 0 auto;
	max-width: 42rem;
	padding-left: 1rem;
	padding-right: 1rem;

img {
	display: block;
	max-width: 100%;

pre {
	border: 1px solid #ccc;
	padding: 1rem;
	overflow: auto;
	-webkit-overflow-scroll: touch;

/* Sticky Header + Backdrop Filter */
.blurry-header {
	position: sticky;
	top: 0;
	padding: 1rem;
	background-color: rgba(255, 255, 255, 0.7);
	backdrop-filter: saturate(180%) blur(10px);

.u-position-relative {
	position: relative;

/* Full Width (aka "Breakout") Container */
/* */
.u-full-width {
  width: 100vw;
  margin-right: calc(50% - 50vw);
  margin-left: calc(50% - 50vw);
  padding-right: calc(50vw - 50%);
  padding-left: calc(50vw - 50%);

/* -------------------------------- */
/* Definition List w/ Leading Lines */
/* */
/* -------------------------------- */

dl {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-column-gap: 1em;
  grid-row-gap: 0.5em;
  margin: 1em;
  line-height: 1.3;

dt {
  position: relative;
  grid-column: 1;
  font-weight: bold;
  overflow: hidden;

dd {
  grid-column: 2;
  margin-left: 0;

dt::after {
  position: absolute;
  top: 0.6em;
  width: 100%;
  margin-left: 0.75em;
  border-bottom: 1px dotted #ccc;
  content: '';