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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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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <main>
	<section>
		<h1>All gradients use the same start and stop colors</h1>

		<input type="checkbox" id="show-extended">
		<label for="show-extended">
			Show all color-interpolation-methods
		</label>

		<h2>srgb</h2>
		<div class="gradient srgb"></div>

		<h2 class="extended">srgb-linear</h2>
		<div class="gradient srgb-linear extended"></div>

		<h2>lab</h2>
		<div class="gradient lab"></div>

		<h2 class="extended">oklab</h2>
		<div class="gradient oklab extended"></div>

		<h2>xyz</h2>
		<div class="gradient xyz"></div>

		<h2 class="extended">xyz-d50</h2>
		<div class="gradient xyz-d50 extended"></div>

		<h2 class="extended">xyz-d65</h2>
		<div class="gradient xyz-d65 extended"></div>

		<h2>hsl</h2>
		<div class="gradient hsl"></div>

		<h2>hwb</h2>
		<div class="gradient hwb"></div>

		<h2>lch</h2>
		<div class="gradient lch"></div>

		<h2>oklch</h2>
		<div class="gradient oklch"></div>
	</section>
</main>
!

CSS 

              
                /**
 * Try changing these colors to see how the
 * different interpolation methods handle it
 * 
 * @see https://oklch.com/
 * @see https://mdn.io/named-color
 */
:root {
	--color-start: oklch(74.11% 0.416 338.29);
	--color-end: oklch(82.46% 0.464 152.87);
}

/**
 * Set each gradient container to use the correct
 * color interpolation method.
 * 
 * @see https://mdn.io/color-interpolation-method
 */
.gradient {
	background: linear-gradient(
		to right in var(--color-interpolation-method),
		var(--color-start),
		var(--color-end)
	);
}

.srgb {
	--color-interpolation-method: srgb;
}

.srgb-linear {
	--color-interpolation-method: srgb-linear;
}

.lab {
	--color-interpolation-method: lab;
}

.oklab {
	--color-interpolation-method: oklab;
}

.xyz {
	--color-interpolation-method: xyz;
}

.xyz-d50 {
	--color-interpolation-method: xyz-d50;
}

.xyz-d65 {
	--color-interpolation-method: xyz-d65;
}

.hsl {
	--color-interpolation-method: hsl;
}

.hwb {
	--color-interpolation-method: hwb;
}

.lch {
	--color-interpolation-method: lch;
}

.oklch {
	--color-interpolation-method: oklch;
}

/******************************************************
 * Additional styles to make the demo look nice.
 *****************************************************/

* {
	box-sizing: border-box;
}

html {
	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica,
		Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
	font-size: 16px;
	line-height: 1.45;
}

body {
	background: radial-gradient(
			circle,
			oklch(0.1 0.15 200 / 0),
			oklch(0.1 0.15 200 / 0.75)
		),
		linear-gradient(344deg in oklch, oklch(0.2 0.1 150), oklch(0.2 0.2 220));
	background-blend-mode: multiply, normal;
	margin: 0;
}

:is(h1, h2) {
	margin: 0;
}

main {
	display: grid;
	gap: 1rem;
	min-height: 100svh;
	place-content: center;
}

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

@keyframes spin {
	to {
		--angle: 360deg;
	}
}

section {
	align-items: center;
	animation: spin 20s linear infinite;
	background: linear-gradient(to bottom, oklch(1 0 220 / 0.95) 0 0) padding-box,
		conic-gradient(
				from var(--angle) in oklch,
				var(--color-start),
				var(--color-end),
				var(--color-start)
			)
			border-box;
	border: 0.125rem solid transparent;
	border-radius: 1rem;
	display: grid;
	gap: 0.25rem 1rem;
	grid-template-columns: 100px 1fr;
	padding: 1rem 2rem 1.5rem;
	position: relative;
	width: min(90vw, 600px);

	&::after {
		animation: spin 20s linear infinite;
		content: "";
		position: absolute;
		inset: 0;
		background: conic-gradient(
			from var(--angle) in oklch,
			var(--color-start),
			var(--color-end),
			var(--color-start)
		);
		filter: blur(3rem);
		opacity: 0.3;
		z-index: -1;
	}

	& h1 {
		font-size: 1.25rem;
		grid-column: span 2;
	}

	& h2 {
		font-size: 1rem;
		text-align: right;
	}

	& .gradient {
		aspect-ratio: 12 / 1;
		border-radius: 0.25rem;
		width: 100%;
	}
}

input {
	margin-block: 0.25rem 1rem;
	margin-inline-start: auto;
}

label {
	margin-block: 0.25rem 1rem;
}

.extended {
	display: none;
}

:checked ~ .extended {
	display: block;
}
!

JS 

              
                // no JS!
!
999px

Console