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                <ol class="clock" role="image">


                * { box-sizing: border-box }

body {
	margin: 0;
	min-height: 100vh;
	display: grid;
	place-items: center;
	background: url( center/cover; /* background image by thomas heintz on Unsplash */

@counter-style upper-roman--iiii {
	range: 4 4;
	system: symbolic;
	symbols: 'I';
	fallback: upper-roman;

.clock {
	--style: upper-roman--iiii;
	container-type: inline-size;
	margin: auto;
	padding: 0;
	aspect-ratio: 1;
	width: clamp(8em, 80vmin, 24em);
	border-radius: 50%;
	background: radial-gradient(black 2%, snow 0);
	outline: thin solid silver;
	box-shadow: .5vmin 1vmin 3vmin gray;
	display: grid;
	list-style: var(--style) inside;

	&:has(li:nth-of-type(1)) { --count: 1 }
	&:has(li:nth-of-type(2)) { --count: 2 }
	&:has(li:nth-of-type(3)) { --count: 3 }
	and so on…
	li:nth-of-type(1) { --index: 1 }
	li:nth-of-type(2) { --index: 2 }
	li:nth-of-type(3) { --index: 3 }
	and so on…
	preprocessor for convenience:
	@for $i from 1 through 12 {
		&:has(li:nth-of-type(#{$i})) { --count: #{$i} }
		& li:nth-of-type(#{$i}) { --index: #{$i} }

	& li {
		font: 10cqw/1 'Alchemist', serif;
		font-variant-numeric: proportional-nums lining-nums;
		grid-column: 1;
		grid-row: 1;
		place-self: center;
		text-align: center;
		height: 100cqw;
		padding: 3cqw;
		--angle: calc(var(--index) / var(--count) * 1turn);
		rotate: var(--angle);

		&::marker {
			content: counter(list-item, var(--style));


                // :has() polyfill
if (!CSS.supports('selector(&:has(li:nth-of-type(1)))')) {
	const setCount = (element) => {'--count', element.childElementCount);

	const countObserver = new MutationObserver(setCount);

	for (let element of document.querySelectorAll('.clock')) {
		countObserver.observe(element, {childList: true});