.content
	- for(i=0; i<2; i++)
		.bars
			- for(b=0; b<7; b++)
				.bar

:root {
	--b: #262626;
	--w: #dcdcd2;
	--s: 2s; /* change speed */
}	

*, *:before, *:after {
	box-sizing: border-box;
	transform-style: preserve-3d;
}

body {
	margin: 0;
	padding: 0;
	width: 100vw;
	height: 100vh;
	overflow: hidden;
	display: flex;
	align-items: center;
	justify-content: center;
	background: var(--b);
}

.content {
	width: 50vmin;
	height: 50vmin;
	text-align: center;
	display: flex;
	align-items: center;
	justify-content: center;
	flex-direction: column;
	perspective: 1000vmin;
}

.bars {
	width: 100%;
	height: 100%;
	position: absolute;
	padding: 6.5vmin 3vmin;
	animation: mirror1 calc(var(--s) * 2) ease 0s infinite ;
}

.bars + .bars {
	transform: rotate(90deg) rotateX(180deg);
	animation: mirror2 calc(var(--s) * 2) ease calc(var(--s) / 2) infinite;
}

.bar {
	width: 44vmin;
	height: 3vmin;
	margin: 2vmin 0vmin;
	background: linear-gradient(90deg, #fff0 33%, var(--w) 33% 67%, #fff0 67% 100%);
	animation: grow var(--s) ease-in-out 0s infinite alternate; 
	background-size: 300%;
	background-position-x: -203%;
}

@keyframes mirror1 {
	0%, 47%, 99.99%, 100% { transform: rotate(180deg) rotateX(0deg); }
	47.01%, 99.98% { transform: rotate(180deg) rotateX(180deg); }
}

@keyframes mirror2 {
	0%, 47%, 99.99%, 100% { transform: rotate(90deg) rotateX(180deg); }
	47.01%, 99.98% { transform: rotate(90deg) rotateX(0deg); }
}

@keyframes grow {
	0%, 25% { background-position-x: -297%; }
	45%, 55% { background-position-x: -250%; }
	75%, 100% { background-position-x: -203%; }
}

.bar:nth-child(2) {
	animation-delay: calc(var(--s) * -0.02);
}
.bar:nth-child(3) {
	animation-delay: calc(var(--s) * -0.04);
}
.bar:nth-child(4) {
	animation-delay: calc(var(--s) * -0.06);
}
.bar:nth-child(5) {
	animation-delay: calc(var(--s) * -0.08);
}
.bar:nth-child(6) {
	animation-delay: calc(var(--s) * -0.1);
}
.bar:nth-child(7) {
	animation-delay: calc(var(--s) * -0.12);
}

.bars:nth-child(2) .bar:nth-child(1) {
	animation-delay: calc(calc(var(--s) * -0.001) - calc(var(--s) / 2));
}
.bars:nth-child(2) .bar:nth-child(2) {
	animation-delay: calc(calc(var(--s) * -0.02) - calc(var(--s) / 2));
}
.bars:nth-child(2) .bar:nth-child(3) {
	animation-delay: calc(calc(var(--s) * -0.04) - calc(var(--s) / 2));
}
.bars:nth-child(2) .bar:nth-child(4) {
	animation-delay: calc(calc(var(--s) * -0.06) - calc(var(--s) / 2));
}
.bars:nth-child(2) .bar:nth-child(5) {
	animation-delay: calc(calc(var(--s) * -0.08) - calc(var(--s) / 2));
}
.bars:nth-child(2) .bar:nth-child(6) {
	animation-delay: calc(calc(var(--s) * -0.1) - calc(var(--s) / 2));
}
.bars:nth-child(2) .bar:nth-child(7) {
	animation-delay: calc(calc(var(--s) * -0.12) - calc(var(--s) / 2));
}

// Insipred by this image from Pinterest:
// https://www.pinterest.com/pin/14425661292261254/