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CSS

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JavaScript

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HTML 

              
                <form>
	<label>
		<input type="radio" name="dummy" value="top" checked> <span>Top</span>
	</label>
	<label>
		<input class="pristine" type="radio" name="dummy" value="middle"> <span>Middle</span>
	</label>
	<label>
		<input class="pristine" type="radio" name="dummy" value="bottom"> <span>Bottom</span>
	</label>
	<br>
	<button type="reset">Reset</button>
</form>
!

CSS 

              
                * {
	border: 0;
	box-sizing: border-box;
	margin: 0;
	padding: 0;
}
:root {
	--fg: #17181c;
	--trans: 0.15s;
	font-size: calc(30px + (40 - 30) * (100vw - 320px) / (1280 - 320));
}
body, button, input {
	font: 1em/1.5 "Hind", sans-serif;
}
body {
	background-color: #79934f;
	color: var(--fg);
	display: flex;
	height: 100vh;
}
button, input, label {
	cursor: pointer;
	-webkit-tap-highlight-color: #0000;
}
button, input {
	-webkit-appearance: none;
	appearance: none;
}
button, input[type=radio]:focus {
	outline: 0;
}
button {
	background-color: #255ff4;
	border-radius: 0.2em;
	color: #fff;
	display: block;
	margin: auto;
	padding: 0.5em 1em;
	transition: background-color var(--trans) linear;
}
button:focus, button:hover {
	background-color: #0b46da;
}
button:active {
	transform: translateY(0.1em);
}
form {
	margin: auto;
	padding: 1.5em 0;
}
input[type=radio], input[type=radio]:before, input[type=radio]:after, .dirt, .dust, .dust-fog {
	border-radius: 50%;
}
input[type=radio]:before, input[type=radio]:after, .dirt, .dust, .dust-fog {
	position: absolute;
}
input[type=radio], label {
	position: relative;
}
input[type=radio] {
	--dur: 0.6s;
	animation: createHole var(--dur) steps(1);
	background-image:
		radial-gradient(1em 1em at 0.5em 0.5em,#b38d56 49%,#b38d5600 50%),
		radial-gradient(1em 1em at 1.5em 0.5em,#2f2215 9%,#523c25 10% 19%,#7c6139 20% 29%,#a8824c 30% 39%,#b38d56 40% 49%,#b38d5600 50%);
	background-position: -1em 0;
	background-repeat: no-repeat;
	background-size: 2em 1em;
	font-size: 2em;
	margin-right: 0.5rem;
	width: 1em;
	height: 1em;
}
input[type=radio]:before, input[type=radio]:after {
	content: "";
	display: block;
	transform: scale(0);
}
input[type=radio]:before {
	animation: burrow var(--dur) linear;
	background-image:
		radial-gradient(100% 100% at center,#45495400 19%,#454954 20% 24%,#818897 25% 39%,#81889700 40%),
		repeating-conic-gradient(from 0 at center,#737a8c 0deg 10deg,#737a8c00 11deg 29deg,#737a8c 30deg 40deg);
	top: 0;
	left: 0;
	width: 100%;
	height: 100%;
}
input[type=radio]:after {
	animation: hubIn var(--dur) linear;
	background-color: #255ff4;
	box-shadow: 0 -0.1em 0 #0b46da inset;
	top: 30%;
	left: 30%;
	width: 40%;
	height: 40%;
}
input[type=radio]:checked:before, input[type=radio]:checked:after {
	transform: scale(1);
}
input[type=radio]:checked:before {
	animation: surface var(--dur) linear;
}
input[type=radio]:checked:after {
	animation: hubOut var(--dur) linear;
}
input[type=radio].pristine, input[type=radio].pristine:before, input[type=radio].pristine:after {
	animation: none;
}
input[type=radio].pristine {
	background-position: 0 0;
}
input[type=radio] + span {
	transition: color var(--trans) linear;
}
input[type=radio]:focus + span {
	color: #dbc9a4;
}
label {
	background-color: #a8824c;
	border-radius: 0.25em;
	box-shadow: 0 0.05em 0 0.05em #5e723d inset;
	display: flex;
	align-items: center;
	margin-bottom: 0.5em;
	padding: 0.25em 0.5em 0.25em 0.25em;
}
.dirt, .dust, .dust-fog {
	display: block;
	top: 50%;
	left: 1.25em;
	pointer-events: none;
}
.dirt {
	background-color: #7c6139;
	width: 0.4em;
	height: 0.4em;
	z-index: 1;
	transform: translate(-0.2em,-0.2em) scale(0);
}
.dust {
	background-color: #ccb380;
	width: 0.8em;
	height: 0.8em;
	z-index: 2;
	transform: translate(-0.4em,-0.4em) scale(0);
}
.dust-fog {
	background-color: #ccb38020;
	width: 1em;
	height: 1em;
	z-index: 3;
	transform: translate(-0.5em,-0.5em) scale(0);
}
/* Animations */
@keyframes burrow {
	from {
		transform: rotate(0turn) scale(1);
	}
	50% {
		transform: rotate(0.5turn) scale(1.2);
	}
	to {
		transform: rotate(1turn) scale(0);
	}
}
@keyframes createHole {
	from {
		background-position: 0 0;
	}
	to {
		background-position: -1em 0;
	}
}
@keyframes hubIn {
	from {
		transform: scale(1);
	}
	50% {
		transform: scale(1.2);
	}
	to {
		transform: scale(0);
	}
}
@keyframes hubOut {
	from {
		transform: scale(0);
	}
	50% {
		transform: scale(1.2);
	}
	to {
		transform: scale(1);
	}
}
@keyframes surface {
	from {
		transform: rotate(0turn) scale(0);
	}
	50% {
		transform: rotate(0.5turn) scale(1.2);
	}
	to {
		transform: rotate(1turn) scale(1);
	}
}
!

JS 

              
                document.addEventListener("DOMContentLoaded",init.bind(document,"dummy"));

function init(inputName) {
	let form = this.forms[0];
	if (form) {
		let prevTar = null,
			inputs = Array.from(this.getElementsByName(inputName));
		// blade popping in and out
		form.addEventListener("change",e => {
			let tar = e.target;
			if (tar) {
				// previous value
				if (prevTar)
					splatterParticles(prevTar,"dirt",25);
				prevTar = tar;
				// current value, use dust particles the first time the radio is checked
				if (tar.classList.contains("pristine")) {
					tar.removeAttribute("class");
					splatterParticles(tar,"dust",60);
					splatterParticles(tar,"dust-fog",15);
				}
				splatterParticles(tar,"dirt",20);
			}
		});
		// set everything back to pristine state
		form.addEventListener("reset",E => {
			prevTar = null;
			inputs.forEach((e,i) => {
				e.className = "pristine";
				e.checked = false;
			});
			E.preventDefault();
		});
		// particles for value on load
		splatterParticles(inputs[0],"dirt",20);
	}
}
function propertyUnitsStripped(el,property,unit) {
	let cs = window.getComputedStyle(el),
		valueRaw = cs.getPropertyValue(property),
		value = +valueRaw.substr(0,valueRaw.indexOf(unit));
	return value;
}
function splatterParticles(target,particleType = "dirt",particleCount = 1) {
	let parent = target.parentElement;
	if (parent) {
		let baseDur = propertyUnitsStripped(target,"--dur","s") * 1000,
			// particle objects
			dirt = {
				dist: {
					start: 0.5,
					min: 1.5,
					max: 2
				},
				diam: {
					min: 0.2,
					max: 0.4
				},
				delay: {
					min: baseDur * 0.25,
					max: baseDur * 0.5
				},
				dur: baseDur,
				end_opacity: 1,
				end_scale: 0
			},
			dust = {
				dist: {
					start: 0,
					min: 2.5,
					max: 3
				},
				diam: {
					min: 0.8,
					max: 1
				},
				delay: {
					min: 0,
					max: 0
				},
				dur: baseDur,
				end_opacity: 0,
				end_scale: 0.5
			},
			dustFog = {
				dist: {
					start: 0,
					min: 1,
					max: 1.5
				},
				diam: {
					min: 1,
					max: 1.5
				},
				delay: {
					min: baseDur * 0.1,
					max: baseDur * 0.2
				},
				dur: baseDur * 4,
				end_opacity: 0,
				end_scale: 1
			},
			// parameters common for all particles
			pObj = particleType == "dust" ? dust : (particleType == "dust-fog" ? dustFog : dirt),
			nearestEm = 0.01,
			distStart = pObj.dist.start,
			dur = pObj.dur,
			endOpacity = pObj.end_opacity,
			endScale = pObj.end_scale;
		// spawn the particles
		for (let i = 0; i < particleCount; ++i) {
			let p = document.createElement("span");
			p.className = particleType;
			parent.appendChild(p);
			// randomized parameters for each particle
			let rot = Math.floor(Math.random() * 360),
				diam = pObj.diam.min + Math.round(Math.random() * (pObj.diam.max - pObj.diam.min) / nearestEm) * nearestEm,
				rad = diam / 2,
				dist = pObj.dist.min + Math.round(Math.random() * (pObj.dist.max - pObj.dist.min) / nearestEm) * nearestEm,
				delay = pObj.delay.min + Math.round(Math.random() * (pObj.delay.max - pObj.delay.min));

			p.style.width = `${diam}em`;
			p.style.height = `${diam}em`;
			// animation
			let transStart = `translate(${-rad}em,${-rad}em) rotate(${rot}deg)`,
				seq = p.animate(
				[
					{
						transform: `${transStart} translateX(${distStart}em) scale(0)`,
						opacity: 1
					},
					{
						transform: `${transStart} translateX(${distStart + (dist - distStart)/2}em) scale(1)`,
						opacity: 1
					},
					{
						transform: `${transStart} translateX(${dist}em) scale(${endScale})`,
						opacity: endOpacity
					}
				],
				{
					duration: dur,
					easing: "cubic-bezier(0.1,0.6,0.4,0.9)",
					delay: delay
				}
			);
			seq.onfinish = p.remove.bind(p);
		}
	}
}
!
999px

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