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HTML

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CSS

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CSS Base

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JavaScript

About JavaScript Preprocessors

JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <svg viewBox="0 0 640 512" width="100" title="fighter-jet" class="progress">
  <path d="M544 224l-128-16-48-16h-24L227.158 44h39.509C278.333 44 288 41.375 288 38s-9.667-6-21.333-6H152v12h16v164h-48l-66.667-80H18.667L8 138.667V208h8v16h48v2.666l-64 8v42.667l64 8V288H16v16H8v69.333L18.667 384h34.667L120 304h48v164h-16v12h114.667c11.667 0 21.333-2.625 21.333-6s-9.667-6-21.333-6h-39.509L344 320h24l48-16 128-16c96-21.333 96-26.583 96-32 0-5.417 0-10.667-96-32z" />
</svg>

<svg viewBox="0 0 640 512" width="0" height="0" title="cloud">
	<defs>
  <path id="cloud" d="M537.6 226.6c4.1-10.7 6.4-22.4 6.4-34.6 0-53-43-96-96-96-19.7 0-38.1 6-53.3 16.2C367 64.2 315.3 32 256 32c-88.4 0-160 71.6-160 160 0 2.7.1 5.4.2 8.1C40.2 219.8 0 273.2 0 336c0 79.5 64.5 144 144 144h368c70.7 0 128-57.3 128-128 0-61.9-44-113.6-102.4-125.4z" />
	</defs>
</svg>

<svg viewBox="0 0 640 512" width="100" title="cloud" class="cloud">
	<use href="#cloud"></use>
</svg>

<svg viewBox="0 0 640 512" width="100" title="cloud" class="cloud">
	<use href="#cloud"></use>
</svg>

<svg viewBox="0 0 640 512" width="100" title="cloud" class="cloud">
	<use href="#cloud"></use>
</svg>
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CSS 

              
                * {
	box-sizing: border-box;
}

body {
	width: 100%;
	min-height: 300vh;
	margin: 0;
	background: linear-gradient(to bottom, #2d2a82, lightblue);
	background-size: 100% 300vh;
}

.progress {
	position: fixed;
	top: 3rem;
	left: 3rem;
	width: 3rem;
	height: auto;
	fill: currentColor;
	z-index: 1;
	offset-path: path('M.5 122.7s24.7-275 276.9 0c327.1 356.7 266.1-330.3 548-33.3 256.9 270.7 271.1 0 271.1 0');
	animation: move auto linear;
	animation-timeline: scroll(root);
}

.cloud {
	width: 12vw;
	height: auto;
	position: absolute;
	top: 5vh;
	left: 60vw;
	fill: rgb(255 255 255 / 0.5);
}

.cloud:nth-child(2n) {
	top: 100vh;
	left: 15vw;
}

.cloud:nth-child(3n) {
	top: 160vh;
	left: 70vw;
}

@keyframes move {
	0% {
		offset-distance: 0%;
	}
	100% {
		offset-distance: 100%;
	}
}
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JS
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