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HTML

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CSS

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CSS Base

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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 colors = [{value:"brown",name:"Brown"},{value:"red",name:"Red"},{value:"orange",name:"Orange"},{value:"yellow",name:"Yellow"},{value:"green",name:"Green"},{value:"lime",name:"Lime"},{value:"cyan",name:"Cyan"},{value:"lightblue",name:"Light Blue"},{value:"blue",name:"Blue"},{value:"purple",name:"Purple"},{value:"magenta",name:"Magenta"},{value:"pink",name:"Pink"},{value:"black",name:"Black"},{value:"gray",name:"Gray"},{value:"lightgray",name:"Light Gray"},{value:"white",name:"White"}];

.cp
	each color, index in colors
		label(class="cp__color cp__color--" + color.value)
			input.cp__color-input(type="radio",name="color",value=color.value,title=color.name,checked=index===0)
			span.cp__sr-only=color.name
!

CSS 

              
                $hue: 223
$colors: ("brown": hsl(23,90%,25%),"red": hsl(3,90%,55%),"orange": hsl(33,90%,55%),"yellow": hsl(53,90%,55%),"green": hsl(78,90%,30%),"lime": hsl(88,90%,55%),"cyan": hsl(183,90%,55%),"lightblue": hsl(198,90%,55%),"blue": hsl(223,90%,55%),"purple": hsl(273,90%,45%),"magenta": hsl(303,90%,55%),"pink": hsl(343,90%,75%),"black": hsl(0,0%,10%),"gray": hsl(0,0%,30%),"lightgray": hsl(0,0%,60%),"white": hsl(0,0%,90%))

*
	border: 0
	box-sizing: border-box
	margin: 0
	padding: 0

\:root
	font-size: calc(12px + (32 - 12) * (100vw - 320px) / (1280 - 320))

body,
input
	font: 1em/1.5 sans-serif

body
	background: linear-gradient(-45deg,#{hsl($hue,10%,90%)},#{hsl($hue,10%,80%)})
	height: 100vh
	min-height: 600px
	display: grid
	overflow-x: hidden
	place-items: center

.cp
	background: linear-gradient(90deg,#{hsl($hue,10%,45%)},#{hsl($hue,10%,65%)})
	border-radius: 2em
	box-shadow: 0.1em 0.1em 0 #{hsl($hue,10%,75%)}, 0.25em 0.25em 0 #{hsl($hue,10%,45%)}, 0.375em 0.375em 0.375em #{hsla($hue,0%,0%,0.6)}
	display: grid
	grid-template-columns: repeat(4,1fr)
	grid-template-rows: repeat(4,1fr)
	width: 16em
	height: 16em
	transform: rotateX(45deg) rotateZ(45deg)

	&__color
		padding: 0.5em
		-webkit-tap-highlight-color: transparent
		&,
		&-input
			display: block
		&-input
			border-radius: 50%
			position: relative
			width: 3em
			height: 3em
			transform: translate3d(-0.5em,-0.5em,0)
				style: preserve-3d
			transition: transform 0.15s linear
			-webkit-appearance: none
			appearance: none
			&:after
				border-radius: inherit
				content: ""
				display: block
				position: absolute
				inset: 0
				transform: translate3d(0.25em,0.25em,-1px)
				transition: box-shadow 0.15s linear
			&:checked
				transform: translate3d(-0.25em,-0.25em,0)
			&:focus
				outline: transparent

		@each $name, $value in $colors
			&--#{$name} &-input
				background-image: linear-gradient(90deg,$value,lighten($value,15%))
				&:after
					background: linear-gradient(0deg,darken($value,10%),darken($value,30%),darken($value,20%))
					box-shadow: 0.25em 0.25em 0.25em hsla(0,0%,0%,0.9), 0.5em 0.5em 0.5em fade-out($value,0.4)
				&:checked
					&:after
						box-shadow: 0 0 0.125em hsla(0,0%,0%,0.9), 0.25em 0.25em 0.25em fade-out($value,0.4)
	&__sr-only
		clip: rect(1px,1px,1px,1px)
		overflow: hidden
		position: absolute
		width: 1px
		height: 1px

/* Dark theme */
@media (prefers-color-scheme: dark)
	body
		background: linear-gradient(-45deg,#{hsl($hue,10%,20%)},#{hsl($hue,10%,10%)})
	.cp
		background: linear-gradient(90deg,#{hsl($hue,10%,20%)},#{hsl($hue,10%,40%)})
		box-shadow: 0.1em 0.1em 0 #{hsl($hue,10%,50%)}, 0.25em 0.25em 0 #{hsl($hue,10%,20%)}, 0.375em 0.375em 0.375em #{hsla($hue,0%,0%,0.6)}
!

JS
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999px

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