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HTML 

              
                <body>
	<div class="wrapper">
		<div class="bg-layers"></div>
		
		<div class="main-layers">
			<div class="window">
				
				<div class="window-bg">
					<div class="guard">
						<div class="mask"></div>
						<div class="face">
							<div class="eyes">
								<div class="left"></div>
								<div class="right"></div>
							</div>
							<div class="eyebrows">
								<div class="left"></div>
								<div class="right"></div>
							</div>
						</div>
						
					</div>
				</div>
				
				<div class="shutter">
					<p class="title">408</p>
					<p class="desc">The server can no longer wait for the request.</p>
				</div>
			</div>
			
			<div class="knocker">
				<div class="knocker-ring">
					<div class="knocker-ring-fix"></div>
				</div>
			</div>
		</div>
	</div>
</body>
!

CSS 

              
                *, *::before, *::after {
	box-sizing: border-box;
}
.pseudo {
	content: "";
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}
.absolute {
	position: absolute;
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}


.wrapper {
	position: relative;
	width: 100vw;
	height: 100vh;
}

.bg-layers {
	@extend .absolute;
	z-index: 10;
	background: repeating-linear-gradient(90deg, #d1a361 0%, #c38936 2%, #d1a361 8%, #503106 8.5%, #824f04 9%, #d1a361 10%)
}

.main-layers {
	position: relative;
	z-index: 20;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	padding: 30px 15px;
	width: 100%;
	height: 100%;
}

.window {
	position: relative;
	overflow: hidden;
	margin-bottom: 40px;
	width: 100%;
	max-width: 400px;
	height: 240px;
	border: 16px inset #894f16;
	box-shadow: 0 0 5px 5px #120a03;
	background: #69c6c9;
}
.window-bg {
	@extend .absolute;
}
.guard {
	position: absolute;
	overflow: hidden;
	top: 30px;
	left: calc(50% - 90px);
	width: 180px;
	height: 100%;
	border-top-left-radius: 50%;
	border-top-right-radius: 50%;
	background: linear-gradient(90deg, #c3dadb 0%, #d8eff1 2%, #d8eff1 3.5%, #fff 4%, #d8eff1 7%, #c3dadb 9%, #a8b8b4 20%, #8396a2 30%, #8396a2 42%, #869aa7 46%, #8396a2 50%, #63839a 60%, #30526a 70%, #000 100%);
	
	.mask {
		position: absolute;
		z-index: 30;
		overflow: hidden;
		top: 50px;
		left: 20px;
		width: calc(100% - 40px);
		height: 80px;
		border-top: 20px solid #20242d;
		border-top-left-radius: 50%;
		border-top-right-radius: 50%;
		box-shadow: inset 3px 2px 6px 2px #2c4c62;
	}
	
	.face {
			position: absolute;
			z-index: 20;
			top: 50px;
			left: 20px;
			width: calc(100% - 40px);
			height: 80px;
			border-top-left-radius: 50%;
			border-top-right-radius: 50%;
			background: linear-gradient(90deg, #e9cead 0%, #502e07 100%);
		}
	
	
	.eyebrows {
		position: absolute;
		width: 80%;
		height: 50%;
		bottom: 10%;
		left: 10%;
		display: flex;
		justify-content: space-between;
		
		.left, .right {
			position: relative;
			top: -12px;
			margin-top: 14px;
			width: 40%;
			height: 50%;
			border-radius: 50%;
			border-top: 4px solid #000;
		}
	}
	
	.eyes {
		position: absolute;
		width: 70%;
		height: 50%;
		bottom: 10%;
		left: 15%;
		display: flex;
		justify-content: space-between;
		
		.left, .right {
			position: relative;
			margin-top: 14px;
			width: 35%;
			height: 50%;
			border-radius: 50%;
			// border: 1px solid;
			border-top: 4px solid;
			border-bottom: 2px solid;
			box-shadow: inset 0 0 30px 0px #dadada;
			
			transition: transform .1s ease;
			
			&::after {
				content: "";
				position: absolute;
				top: -3px;
				left: calc(50% - 9px);
				width: 18px;
				height: 15px;
				background: #000;
				border-radius: 50%;
			}
		}
	}
}

.shutter {
	@extend .absolute;
	z-index: 100;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	border-top: 5px solid #69c6c9;
	border-bottom: 5px solid #69c6c9;
	border-right: 5px solid #4d3204;
	border-left: 5px solid #4d3204;
	background: linear-gradient(0deg, #000 0%, #4d3204 5%, #a68a5b 10%, #b69349 50%, #a68a5b 90%, #4d3204 95%, #000 100%);
		
	p {
		margin: 0;
		max-width: 80%;
		font-family: monospace;
		font-weight: 400;
		font-size: 22px;
		text-align: center;
		color: #000;
		text-shadow: .5px .5px 1px #fce0a6;
		opacity: 0;
	}
	
	.title {
		font-size: 40px;
	}
}

.knocker {
	position: relative;
	cursor: pointer;
	transform-origin: top center;
	// transform: rotateX(60deg);
	
	.knocker-ring {
		position: relative;
		z-index: 50;
		width: 120px;
		height: 120px;
		background: radial-gradient(circle at center, transparent 0%, transparent 50%, #120a03 50%, #120a03 53.5%, #06212d 53.8%, #041b25 54%, #4d1a04 58%, #472707 60%, #894f16 64%, #120a03 70%, #120a03 100%);
		// border: 30px solid #ccc;
		border-radius: 50%;
		
			&::after {
				content: "";
				position: absolute;
				z-index: 75;
				top: 5%;
				left: 5%;
				width: 90%;
				height: 90%;
				border-radius: 50%;
				border-left: 5px solid #fabf43;
				opacity: .75;
			}

			&::before {
				content: "";
				position: absolute;
				z-index: 25;
				top: -10px;
				left: calc(50% - 10px);
				width: 30px;
				height: 65px;
				border-radius: 30% / 50%;
				box-shadow: 0 0 20px 10px #16040b;
			}
	}
	
	.knocker-ring-fix {
		position: absolute;
		z-index: 100;
		top: -20px;
		left: calc(50% - 20px);
		width: 40px;
		height: 80px;
		border-radius: 30% / 50%;
		border-top: 2px solid #120a03;
		border-bottom: 2px solid #120a03;
		border-left: 3px solid #fabf43;
		border-right: 5px solid #120a03;
		background: linear-gradient(90deg, #fabf43 0%, #894f16 10%, #894f16 35%, #4d1a04 80%, #041b25 100%);
	}
	
	&::before,
	&::after {
		content: "";
		position: absolute;
		border-radius: 50%;
		z-index: 25;
	}
	
	&::before {
		top: 8%;
		left: 8%;
		width: 90%;
		height: 90%;
		box-shadow: 0 0 30px 15px #16040b;
	}
	&::after {
		top: 5%;
		left: 10%;
		width: 90%;
		height: 90%;
		box-shadow: inset 0 0 30px 20px #16040b;
	}
}

.closing .eyes {
	animation: wink 4s ease forwards 2s;
}
.shutter.open {
	transition: transform .5s ease-out;
	transition-delay: 1.25s;
	transform: translateX(-100%)
}
.closing .shutter {
	animation: close .5s ease-in 5.75s forwards;
}
.closing .shutter p {
	transition: opacity .2s ease;
	transition-delay: 6.5s;
	opacity: 1;
}
.knocker.active {
	animation: knock 1s ease;
}

@keyframes knock {
	35% {
		transform: rotate(10deg)
	}
	65% {
		transform: rotate(-10deg)
	}
}
@keyframes wink {
	0% {
		transform: scaleY(1)
	}
	13% {
		transform: scaleY(1)
	}
	15% {
		transform: scaleY(.1)
	}
	17% {
		transform: scaleY(1)
	}
	48% {
		transform: scaleY(1)
	}
	50% {
		transform: scaleY(.1)
	}
	52% {
		transform: scaleY(1)
	}
	58% {
		transform: scaleY(1)
	}
	60% {
		transform: scaleY(.1)
	}
	62% {
		transform: scaleY(1)
	}
	75% {
		transform: scaleY(1)
	}
	78% {
		transform: scaleY(.6)
	}
	100% {
		transform: scaleY(.6)
	}
}
@keyframes close {
	0% {
		transform: translateX(-100%)
	}
	100% {
		transform: translateX(0)
	}
}
@keyframes open {
	100% {
		transform: translateX(-100%)
	}
}
!

JS 

              
                "use strict";

var knocker = document.querySelector('.knocker');
var shutter = document.querySelector('.shutter');
var wrap = document.querySelector('.wrapper');

knocker.addEventListener('click', knock);

function knock() {
	knocker.classList.remove('active');
	shutter.classList.remove('open');
	wrap.classList.remove('closing');
	
	
	//trick for restarting the animation
	void knocker.offsetWidth;
	void shutter.offsetWidth;
	void wrap.offsetWidth;
	
	knocker.classList.add('active');
	shutter.classList.add('open');
	wrap.classList.add('closing');
}

document.addEventListener('DOMContentLoaded', function() {
	knocker.click();
})
!
999px

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