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About the <head>

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Insecure Resource

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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <ol style="--sibling-count: 50;">
	<li style="--sibling-index: 0;"></li>
	<li style="--sibling-index: 1;"></li>
	<li style="--sibling-index: 2;"></li>
	<li style="--sibling-index: 3;"></li>
	<li style="--sibling-index: 4;"></li>
	<li style="--sibling-index: 5;"></li>
	<li style="--sibling-index: 6;"></li>
	<li style="--sibling-index: 7;"></li>
	<li style="--sibling-index: 8;"></li>
	<li style="--sibling-index: 9;"></li>
	<li style="--sibling-index: 10;"></li>
	<li style="--sibling-index: 11;"></li>
	<li style="--sibling-index: 12;"></li>
	<li style="--sibling-index: 13;"></li>
	<li style="--sibling-index: 14;"></li>
	<li style="--sibling-index: 15;"></li>
	<li style="--sibling-index: 16;"></li>
	<li style="--sibling-index: 17;"></li>
	<li style="--sibling-index: 18;"></li>
	<li style="--sibling-index: 19;"></li>
	<li style="--sibling-index: 20;"></li>
	<li style="--sibling-index: 21;"></li>
	<li style="--sibling-index: 22;"></li>
	<li style="--sibling-index: 23;"></li>
	<li style="--sibling-index: 24;"></li>
	<li style="--sibling-index: 25;"></li>
	<li style="--sibling-index: 26;"></li>
	<li style="--sibling-index: 27;"></li>
	<li style="--sibling-index: 28;"></li>
	<li style="--sibling-index: 29;"></li>
	<li style="--sibling-index: 30;"></li>
	<li style="--sibling-index: 31;"></li>
	<li style="--sibling-index: 32;"></li>
	<li style="--sibling-index: 33;"></li>
	<li style="--sibling-index: 34;"></li>
	<li style="--sibling-index: 35;"></li>
	<li style="--sibling-index: 36;"></li>
	<li style="--sibling-index: 37;"></li>
	<li style="--sibling-index: 38;"></li>
	<li style="--sibling-index: 39;"></li>
	<li style="--sibling-index: 40;"></li>
	<li style="--sibling-index: 41;"></li>
	<li style="--sibling-index: 42;"></li>
	<li style="--sibling-index: 43;"></li>
	<li style="--sibling-index: 44;"></li>
	<li style="--sibling-index: 45;"></li>
	<li style="--sibling-index: 46;"></li>
	<li style="--sibling-index: 47;"></li>
	<li style="--sibling-index: 48;"></li>
	<li style="--sibling-index: 49;"></li>
</ol>

<!-- 
this code generates the above. Also add the import to the JS 
import "https://unpkg.com/@bigandy/sibling-count";

<sibling-count>
	<ol>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
		<li></li>
	</ol>
</sibling-count> -->
!

CSS 

              
                @layer setup, demo;

@layer demo {
	li {
		--_break-after-x-items: var(--break-after-x-items, 10);
		--_per-item-move: var(--per-item-move, 0);
		--_per-item-angle: var(--per-item-angle, 0);
		--_per-item-angle-color: var(--per-item-angle-color, 5);

		--multiplier: mod(var(--sibling-index), var(--_break-after-x-items));

		translate: calc(var(--multiplier) * var(--_per-item-move) * 1px);
		rotate: calc(var(--multiplier) * var(--_per-item-angle) * 1deg);

		background: hsl(
			calc(var(--multiplier) * var(--_per-item-angle-color) * 1deg) 100% 50%
		);

		/* Want to add a margin-bottom every x items, but without nth-child()	 */
		/* use a clamp() : https://stackoverflow.com/a/64322555		 */

		/* using - 2 because we're using index 0, and also want to add the margin under the item before we are breaking, so 2 before the break-after-x-items */
		--number-to-compare: calc(var(--_break-after-x-items) - 2);
		--large-number: var(--_break-after-x-items);

		--add-margin: clamp(
			0,
			(var(--multiplier) - var(--number-to-compare)) * var(--large-number),
			1
		);

		margin-bottom: calc(var(--add-margin) * 20px);
	}
}

@layer setup {
	ol {
		padding-inline: 0;
		max-inline-size: 300px;
		margin-inline-start: 3rem;
		margin-block: 3rem;

		li {
			height: 10px;
			list-style-type: ""; /* Yes this is a hack to hide the numbers */
			transform-origin: 0 0;

			transition: --rotate 1000ms ease-in-out;
		}
	}

	html {
		scrollbar-gutter: stable;
	}
}
!

JS 

              
                // import "https://unpkg.com/@bigandy/sibling-count@0.2.0/sibling-count.js";

// The custom control panel
import { Pane } from "https://cdn.jsdelivr.net/npm/tweakpane@4.0.5/dist/tweakpane.min.js";

const CTRL = new Pane({
	title: "Controls",
	expanded: true
});

const CONFIG = {
	breakPoint: 10,
	perItemMove: 0,
	perItemAngle: 0,
	perItemAngleColor: 5
};

CTRL.addBinding(CONFIG, "breakPoint", {
	min: 1,
	max: 50,
	step: 1,
	label: "Break after x items"
});

CTRL.addBinding(CONFIG, "perItemMove", {
	min: 0,
	max: 100,
	step: 1,
	label: "Per Item Move (px)"
});

CTRL.addBinding(CONFIG, "perItemAngle", {
	min: 0,
	max: 20,
	step: 0.1,
	label: "Per Item Move (deg)"
});

CTRL.addBinding(CONFIG, "perItemAngleColor", {
	min: 0,
	max: 100,
	step: 1,
	label: "Per Item Color (deg)"
});

const syncVarsToDocumentRoot = () => {
	const documentRootStyle = document.documentElement.style;

	documentRootStyle.setProperty("--break-after-x-items", CONFIG.breakPoint);

	documentRootStyle.setProperty("--per-item-move", CONFIG.perItemMove);

	documentRootStyle.setProperty("--per-item-angle", CONFIG.perItemAngle);

	documentRootStyle.setProperty(
		"--per-item-angle-color",
		CONFIG.perItemAngleColor
	);
};

CTRL.on("change", syncVarsToDocumentRoot);
syncVarsToDocumentRoot();
!
999px

Console