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HTML

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

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Vendor Prefixing

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                - var n = 50;

.canvas
	.iso
		while n--
			//- relative initial x axis position
			- var rx0 = +Math.random().toFixed(2);
			//- relative scale
			- var rs = +(1 + Math.random()).toFixed(2);
			//- float up duration
			- var ty = +(5 + 8*Math.random()).toFixed(2);
			//- float up delay
			- var dty = +(Math.random()*-ty).toFixed(2);
			//- float lateral duration
			- var tx = +(3 + 4*Math.random()).toFixed(2);
			//- max horizontal scale
			- var sx = +(1 + .5*Math.random()).toFixed(2);
			//- horizontal scale duration
			- var tsx = +(1 + Math.random()).toFixed(2);
			//- horizontal scale delay
			- var dtsx = +(Math.random()*-tsx).toFixed(2);
			//- max vertical scale
			- var sy = +(1 + .35*Math.random()).toFixed(2);
			//- vertical scale duration
			- var tsy = +(1 + Math.random()).toFixed(2);
			//- vertical scale delay
			- var dtsy = +(Math.random()*-tsy).toFixed(2);
			//- rotation duration
			- var ta = +(4 + 5*Math.random()).toFixed(2);
			//- vertical scale delay
			- var dta = +(Math.random()*-ta).toFixed(2);
			.bubble(style=`--rx0: ${rx0}; --rs: ${rs}; --tx: ${tx}s; --ty: ${ty}s; --dty: ${dty}s; --fx: ${sx}; --tsx: ${tsx}s; --dtsx: ${dtsx}s; --fy: ${sy}; --tsy: ${tsy}s; --dtsy: ${dtsy}s; --ta: ${ta}s; --dta: ${dta}s`)
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CSS 

              
                $r: 2em;
$sa: 5deg;
$rw: radial-gradient(#fff, rgba(#fff, 0) 25%);

@function stop-list($precision: 12) {
	$list: ();
	$unit: 360/$precision;
	
	@for $i from 0 through $precision {
		$list: $list, hsl($i*$unit, 100%, 71%);
	}
	
	@return $list;
}

@property --a { 
		syntax: '<angle>';
	initial-value: 0deg;
	inherits: false
}

@property --x { 
	syntax: '<length>';
	initial-value: 0px;
	inherits: false
}

@property --y { 
	syntax: '<length>';
	initial-value: 0px;
	inherits: false
}

@property --sx { 
	syntax: '<number>';
	initial-value: 1;
	inherits: false
}

@property --sy { 
	syntax: '<number>';
	initial-value: 1;
	inherits: false
}

*, :before, :after {
	box-sizing: border-box;
	margin: 0;
	padding: 0;
}

html {
	overflow: hidden;
}

body {
	&:before {
		position: absolute;
		top: 0; right: 0; bottom: 0; left: 0;
		background: $rw, 
			conic-gradient(stop-list());
		animation: a 5s linear infinite;
		content: '';
		
		@supports (r: 2px) {
			background: $rw, 
				conic-gradient(from var(--a, 0deg), stop-list());
			
			@at-root {
				p {
					display: none;
					position: absolute;
					bottom: 0;
					padding: .5em;
					background: lemonchiffon;
					color: #000;
					font: 600 1.125em segoe script, comic sans ms, cursive;
					
					code {
						color: mediumvioletred;
						font-family: consolas, monaco, monospace
					}
					
					strong {
						color: purple;
						font-weight: 900;
						text-shadow: 1px 0 currentcolor
					}
				}
			}
		}
	}
}

@keyframes a { to { --a: 1turn } }

.canvas {
	position: relative;
	height: 100vh;
	background: #000;
	mix-blend-mode: multiply;
	filter: contrast(10)
}

.iso { isolation: isolate }

.bubble {
	--r: calc(var(--rs)*#{$r});
	--x0: calc(var(--rx0)*(100vw - 2*var(--r)));
	position: absolute;
	top: calc(-2.5*var(--r)); left: var(--x0);
	padding: var(--r);
	border-radius: 50%;
	transform: 
		translate(var(--x, 0px), var(--y, calc((var(--fx) - 1)*200vh)))
		rotate(var(--a, 0deg))
		scale(var(--sx, 1), var(--sy, 1));
	box-shadow: inset 0 0 0 .75em #fff;
	filter: blur(9px);
	background: #000;
	mix-blend-mode: multiply;
	animation: 
		x var(--tx) ease-in-out alternate infinite, 
		y var(--ty) ease-out var(--dty) infinite, 
		sx var(--tsx) ease-in-out var(--dtsx) infinite alternate,  
		sy var(--tsy) ease-in-out var(--dtsy) infinite alternate, 
		a var(--ta) linear var(--dta) infinite
}

@keyframes x {
	0% { --x: calc(-1*var(--r)) }
	100% { --x: calc(var(--r)) }
}

@keyframes y {
	0% { --y: calc(100vh + 3*var(--r)) }
	100% { --y: 0px }
}

@keyframes sx { to { --sx: var(--fx) } }

@keyframes sy { to { --sy: var(--fy) } }
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JS
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999px

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