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HTML

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CSS

About CSS Preprocessors

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

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

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JavaScript

About JavaScript Preprocessors

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

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Using packages here is powered by esm.sh, which makes packages from npm not only available on a CDN, but prepares them for native JavaScript ESM usage.

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HTML 

              
                <form>
	<input id="one" type="radio" name="radios" value="one">
	<input id="two" type="radio" name="radios" value="two">
	<input id="three" type="radio" name="radios" value="three">
	<input id="four" type="radio" name="radios" value="four">
	<span></span>
	<label for="one">One</label>
	<label for="two">Two</label>
	<label for="three">Three</label>
	<label for="four">Four</label>
</form>
!

CSS 

              
                $lightBg: "https://assets.codepen.io/416221/light_wood.jpeg"
$darkBg: "https://assets.codepen.io/416221/dark_wood.jpeg"
$dur: 0.5s

*
	border: 0
	box-sizing: border-box
	margin: 0
	padding: 0
\:root
	font-size: calc(32px + (40 - 32)*(100vw - 320px)/ (1024 - 320))
body
	background:
		image: url($lightBg)
		position: 50% 50%
	color: #381803
	display: flex
	font: 1em Nunito, sans-serif
	height: 100vh
	line-height: 1.5
form
	margin: auto
	max-width: 10em
	padding: 1.5em 0
	position: relative
	label:before, span:before
		border-radius: 50%
		content: ""
	label
		cursor: pointer
		display: flex
		letter-spacing: 0.1em
		text-transform: uppercase
		&:before
			background: radial-gradient(100% 100% at 33% 33%,rgba(0,0,0,0.25) 25%,rgba(0,0,0,0) 50%), radial-gradient(100% 100% at 67% 67%,rgba(255,255,255,0.15),rgba(255,255,255,0) 50%)
			box-shadow: 0 0 0.75em #000 inset
			display: inline-block
			margin-right: 0.375em
			width: 1.5em
			height: 1.5em
		&:not(:last-of-type)
			margin-bottom: 1.5em
	span
		position: absolute
		top: 1.75em
		left: 0.25em
		width: 1em
		height: 1em
		transition: transform $dur/2 linear
		z-index: 1
		&, &:before
			display: block
		&:before
			background:
				color: #2762f3
				image: radial-gradient(10% 10% at 50% 50%, rgba(255,255,255,0.6) 50%, rgba(255,255,255,0)), radial-gradient(12% 12% at 60% 25%, rgba(255,255,255,0.6) 50%, rgba(255,255,255,0)), radial-gradient(100% 100% at 60% 50%, rgba(0,0,0,0) 25%, rgba(0,0,0,0.25) 50%)
			border-radius: 50%
			box-shadow: 0 0.1em 0.1em 0 rgba(0,0,0,0.5), 0 0 0.1em 0.1em rgba(0,0,0,0.25) inset
			width: 100%
			height: 100%

input
	position: fixed
	top: -1.5em
	left: -1.5em

@for $s from 1 through 4
	$yPos: 3em * ($s - 1)
	input:nth-of-type(#{$s}):checked ~ span
		transform: translateY($yPos)
		&:before
			animation: wobble#{$s} $dur linear forwards
	@keyframes wobble#{$s}
		from, to
			transform: translateY(0) scale(1)
		25%
			transform: translateY(0) scale(1.33)
		50%
			transform: translateY(0.25em) scale(1)
		67%
			transform: translateY(-0.15em) scale(1)
		83%
			transform: translateY(0.07em) scale(1)

/* Dark mode */
@media screen and (prefers-color-scheme: dark)
	body
		background:
			image: url($darkBg)
		color: #c58b50
!

JS
!
999px

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