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CSS

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JavaScript

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HTML 

              
                <main>
	<h1>Better Motion</h1>
	<p>Be sure to keep accessibility in mind when designing for motion</p>
	<button data-toggle hidden>
		<span class="button__text" data-btn-text>Turn off motion</span>
		<span class="button__toggle"></span>
	</button>
</main>

<div class="circle"></div>
<div class="circle"></div>
<div class="circle"></div>
<div class="circle"></div>
<div class="circle"></div>
<div class="circle"></div>
!

CSS 

              
                * {
	box-sizing: border-box;
}

:root {
	--buttonColor: #ff1fb0;
}

body {
	font-family: 'Spectral', serif;
	font-size: clamp(100%, 1rem + 2vw, 2rem);
	margin: 0;
	background: #2c67d4;
	color: #ffffff;
	min-height: 100vh;
	max-width: 100%;
	overflow-x: hidden;
	display: flex;
	justify-content: center;
	align-items: center;
}

main {
	width: 100%;
	max-width: 86rem;
	padding: 2rem;
	position: relative;
	z-index: 1;
}

h1 {
	font-weight: 200;
	font-size: clamp(4rem, 10vw, 12rem);
	line-height: 1.2;
	letter-spacing: -0.07em;
	margin: 0;
}

p {
	margin: 0 0 2rem;
}

button {
	display: flex;
	align-items: center;
	justify-content: center;
	border: none;
	padding: 1rem 1.5rem;
	border-radius: 0.4rem;
	font-size: 1.15rem;
	font-family: Helvetica, sans-serif;
	font-weight: 600;
	background-color: var(--buttonColor);
	color: inherit;
	box-shadow: 0 0.1rem 0.85rem rgba(0, 0, 0, 0.25);
	cursor: pointer;
	min-width: 16rem;
	transition: color 200ms, background-color 200ms;
}

button:is(:hover, :focus) {
	--buttonColor: #bf0d81;
}

.button__toggle {
	display: block;
	position: relative;
	flex: 0 0 2.4rem;
	height: 1.5rem;
	border: 2px solid;
	border-radius: 1.5rem;
	margin-left: 0.5rem;
	padding: 4px;
	transform: background-color 100ms 200ms;
}

.button__toggle::after {
	position: absolute;
	width: calc(1.5rem - 10px);
	height: calc(1.5rem - 10px);
	top: 3px;
	left: 3px;
	background-color: #ffffff;
	content: '';
	border-radius: 50%;
	transition: transform 300ms, background-color 300ms;
	transform-origin: center center;
}

.button__text {
	flex: 0 0 auto;
}

.circle {
	--c1: #f2c4e2;
	--c2: #d97eb9;
	--size: max(8rem, 13vw);
	--delay: 0s;
	position: absolute;
	top: 0;
	left: 0;
	width: var(--size);
	height: var(--size);
	border-radius: 50%;
	background: radial-gradient(circle at 20% 70%, var(--c1), var(--c2));
	pointer-events: none;
	animation: var(--animation, drift) 12s var(--delay) linear infinite alternate;
	animation-play-state: var(--playState, paused);
}

@media (prefers-reduced-motion: no-preference) {
	body {
		--playState: running;
	}
}

.allow-motion .button__toggle {
	background-color: #ffffff;
}

.allow-motion .button__toggle::after {
	transform: translate3d(100%, 0, 0) scale(1.2);
	background-color: var(--buttonColor);
}

/* Circle animations */
.circle:nth-child(2) {
	--c1: #194aa6;
	--c2: #194aa6;
	--size: max(3rem, 10vw);
	--delay: 1s;
	top: 50%;
	left: 25%;
}

.circle:nth-child(3) {
	--c1: #194aa6;
	--c2: #194aa6;
	--size: max(3rem, 10vw);
	--delay: 3s;
	top: 30%;
	left: 50%;
}

.circle:nth-child(4) {
	--c1: #a0e3f2;
	--c2: #2fa7c2;
	--animation: drift2;
	--delay: 5s;
	top: 70%;
	left: 20%;
}

.circle:nth-child(5) {
	--animation: drift2;
	--delay: 4s;
	top: 60%;
	left: 70%;
}

.circle:nth-child(6) {
	--c1: #a0e3f2;
	--c2: #2fa7c2;
	--delay: 7s;
	top: 15%;
	left: 80%;
}


@keyframes drift {
	50% {
		transform: translate3d(50%, 50%, 0);
	}
	100% {
		transform: translate3d(0, 100%, 0);
	}
}

@keyframes drift2 {
	50% {
		transform: translate3d(-50%, -50%, 0);
	}
	100% {
		transform: translate3d(0, -100%, 0);
	}
}
!

JS 

              
                const toggle = document.querySelector('[data-toggle]')
const buttonText = document.querySelector('[data-btn-text]')
const prefersReducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)')

const setReducedMotionStyles = () => {
	buttonText.innerText = 'Turn on motion'
	document.body.classList.remove('allow-motion')
	document.body.style.setProperty('--playState', 'paused')
}

const setMotionStyles = () => {
	buttonText.innerText = 'Turn off motion'
	document.body.classList.add('allow-motion')
	document.body.style.setProperty('--playState', 'running')
}

const getMotionPreference = () => {
	const localStoragePreference = localStorage.getItem('prefersReducedMotion')
	
	// First check localStorage, to see if the user has previously stated a preference
	if (localStoragePreference) {
		return localStoragePreference
	} else {
		// Otherwise, check the user's system preferences
		return prefersReducedMotion.matches ? 'reduce' : 'no-preference'
	}
}

const setInitialStyles = () => {
	// Otherwise, check the user's system preferences
	if (getMotionPreference() == 'reduce') {
		setReducedMotionStyles()
	} else {
		setMotionStyles()
	}
	
	// The button is hidden initially, as it won't work without JS. We need to make it visible
	toggle.hidden = false
}

setInitialStyles()

toggle.addEventListener('click', () => {
	if (getMotionPreference() == 'reduce') {
		// If currently set to reduced motion, toggle motion on
		localStorage.setItem('prefersReducedMotion', 'no-preference')
		setMotionStyles()
	} else {
		// Otherwise, toggle motion off
		localStorage.setItem('prefersReducedMotion', 'reduce')
		setReducedMotionStyles()
	}
})
!
999px

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