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HTML 

              
                <progress-indicator aria-valuenow="25"></progress-indicator>
!

CSS 

              
                /* normally I would install form fontsource, but it's a demo */
@import url('https://fonts.googleapis.com/css2?family=Space+Mono:ital,wght@0,400;0,700;1,400;1,700&display=swap');

/* not supported by Firefox yet, but progressively enhance with ring transition animation */
@property --progress-value {
	syntax: "<number>";
	inherits: true;
	initial-value: 1;
}

:root {
	--font-base: 'Space Mono', monospace;
	--color-dark: #1f1a38;
	--color-dark-glare: #989ea9;
	--color-success: #76f7bf;
}

body {
	box-sizing: border-box;
}

progress-indicator {
	--progress-value: 1; /* start with either 1 or 0 so there’s no partial ring without JS */

	display: inline-grid;
	font-family: var(--font-base);
	font-size: 2rem;
	color: black;
	--radius: 2.09375em; /* should the whole thing scale uniformly with font size? I say yes. */
	width: calc(var(--radius) * 2);
	aspect-ratio: 1;
	border-radius: 50%;
	overflow: hidden;
	--progress-bar-thickness: .3125em;
	transition: --progress-value 50ms;

	&::before, &::after {
		grid-area: 1 / 1 / -1 / -1;
	}

	&::before {
		content: "";
		/* the ring value */
		background-image: conic-gradient(
			var(--color-dark) calc(var(--progress-value) * 1turn),
			calc(var(--progress-value) * 1turn),
			var(--color-dark-glare)
		);

		/* make it a ring instead of a whole circle */
		mask: radial-gradient(
			transparent,
			calc(var(--radius) - var(--progress-bar-thickness)),
			black calc(var(--radius) - var(--progress-bar-thickness)),
			black
		);
	}

	&::after {
		display: grid;
		place-content: center;
		/* place-self: center; */
		content: attr(aria-valuenow)"%"; /* this value will never get updated without JS, but might as well show what got sent over the wire */
	}

	&[aria-valuenow="100"]::before {
		background-image: none;
		mask: none;
		background-color: var(--color-success);
		border-radius: inherit;
		border: var(--progress-bar-thickness) solid black;
	}

	&[aria-valuenow="100"]::after {
		background-color: black;
		mask: url('data:image/svg+xml;utf8,<svg width="85" height="85" viewBox="0 0 85 85" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="M35.4237 53.7327L67.9787 21.1777L72.9895 26.1842L35.4195 63.75L12.886 41.2122L17.8925 36.2015L35.4237 53.7327Z" fill="black"/></svg>');
		mask-repeat: no-repeat;
		mask-position: center;
		mask-size: 2.65625em;
	}
}
!

JS 

              
                // a custom element that just watches the `aria-valuenow` attribute and sets a CSS custom prop for the ring
class ProgressIndicator extends HTMLElement {
	static observedAttributes = ["aria-valuenow"];

	attributeChangedCallback(name, oldValue, newValue) {
		if(name === "aria-valuenow") {
			this.style.setProperty("--progress-value", parseFloat(newValue)/100);

			// when resetting to 0, don’t do trannsition animation
			if(oldValue === "100" && newValue === "0") {
				this.style.setProperty("transition", "none");
			}
			else {
				this.style.setProperty("transition", "");
			}
		}
	}

	static {
		customElements.define("progress-indicator", this);
	}
}







// demo stuff
const pi = document.querySelector("progress-indicator");
const duration = 3000;
const wait = 1000;
let startTime, elapsedTime;
const tick = t => {
	if(startTime === undefined) startTime = t;
	elapsedTime = t - startTime;
	pi.setAttribute("aria-valuenow", Math.min(Math.round(elapsedTime/duration * 100), 100));
	if(elapsedTime > duration + wait) {
		startTime = undefined;
	}
	requestAnimationFrame(tick);
}
requestAnimationFrame(tick);
!
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