<div class="container"></div>
body {
	background: url(https://images.unsplash.com/photo-1544306094-e2dcf9479da3) no-repeat;
	/* Keep the inherited background full size. */
	background-attachment: fixed; 
	background-size: cover;
	display: grid;
	align-items: center;
	justify-content: center;
	height: 100vh;
}

.container {
	width: 30rem;
	height: 20rem;
	box-shadow: 0 0 1rem 0 rgba(0, 0, 0, .2);	
	border-radius: 5px;
	position: relative;
	z-index: 1;
	background: inherit;
	overflow: hidden;
}

.container:before {
	content: "";
	position: absolute;
	background: inherit;
	z-index: -1;
	top: 0;
	left: 0;
	right: 0;
	bottom: 0;
	box-shadow: inset 0 0 2000px rgba(255, 255, 255, .5);
	filter: blur(10px);
	margin: -20px;
}

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