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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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Adding Classes

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <input type="checkbox" id="switcher">
<div class="body">
	<article>

		<h1>Hello World</h1>
		<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Praesentium architecto tempora deserunt saepe reiciendis ex quia earum nobis, illo quidem non, libero, hic reprehenderit. Error quos quo ad a? Consectetur reiciendis nobis ex molestiae officia perferendis vel quam nemo dolores, consequuntur magnam consequatur accusantium enim, similique quia. At, fuga? Deleniti, consectetur tenetur? Quibusdam eveniet asperiores facilis ab distinctio unde animi placeat et autem pariatur maiores iure enim itaque quisquam quia voluptatibus iste, aspernatur optio tempora consequatur fugiat. Dolorem dolor sint quod rem, veritatis, tempore ea nostrum ratione blanditiis assumenda similique modi mollitia corporis deserunt? Amet placeat nostrum modi, unde facere iusto officiis at odit tenetur! Nisi, veritatis vel ipsum atque nulla facere! Dolorum dolor est quibusdam consequuntur architecto odio fugiat.</p>
		<p>Voluptatum, mollitia. Iure hic id exercitationem corrupti, repellat saepe illum voluptatum molestiae. Laborum hic ea quasi ex ab sapiente quidem iusto, quod fugit nesciunt ducimus, unde consequuntur labore quas eaque rerum exercitationem perspiciatis incidunt dolorem. Ad quisquam eaque, eveniet sequi, deserunt cumque perferendis, nisi distinctio cupiditate error maxime. Culpa nobis voluptatibus libero porro sapiente quo ut atque blanditiis dolore fuga quisquam commodi officiis ratione minus quas, dicta officia eius repellat aperiam debitis alias maxime repellendus! Earum facere ex, maxime repellendus suscipit consequuntur. Temporibus, inventore. Asperiores in maiores, adipisci nulla, nobis ratione laboriosam architecto quas distinctio velit at sed ullam quo iste, eaque odio. Saepe quis itaque quod veniam nemo! Doloremque voluptas modi sit quaerat. Explicabo tempore officiis quidem sint qui.</p>
		<p>Voluptatum nostrum odio aspernatur ullam voluptatibus a porro culpa excepturi. Omnis enim laudantium provident! Ut molestias, sunt temporibus molestiae possimus qui quod repudiandae laborum et sequi tempore quas eum? Magnam error cupiditate repudiandae quasi ullam officiis debitis facilis molestiae? Doloribus hic id eum expedita iste unde, beatae, sint reiciendis velit, blanditiis officiis tempore dicta. Neque quasi nam voluptatibus adipisci esse doloremque quisquam quae incidunt perspiciatis sequi nostrum fuga exercitationem, in accusantium minima facilis iure id error nobis. Veritatis eius amet laudantium dolore culpa vero sequi possimus aperiam ipsam sit. Aperiam vero debitis culpa explicabo perferendis ipsa illum incidunt sint error numquam quidem pariatur, ex molestias porro dolor, laboriosam sunt accusamus qui quas voluptatibus illo amet voluptate reprehenderit voluptas. Perferendis, ea?</p>
		<p>Dolore laudantium amet, possimus ad debitis ipsam quia, rem veniam eligendi laboriosam praesentium, sed saepe labore. Sapiente facere, veritatis impedit ipsum tempore sint cum eaque eos? Doloribus adipisci optio voluptatem minus provident est quod rerum ipsam praesentium hic corrupti reiciendis ut possimus sequi delectus, saepe quas consectetur recusandae odio reprehenderit quasi! Alias non quidem magnam. Et magni deserunt iure impedit tenetur veritatis repudiandae mollitia maiores reiciendis eveniet autem veniam quod dolore vel amet aut esse neque asperiores, ut itaque. Tempora vero optio velit quia vitae quas. Voluptates quisquam aliquid provident itaque optio tempore eligendi aut, obcaecati minus architecto qui suscipit, consequuntur labore accusantium, laudantium reiciendis ea. Non, quae, maiores nesciunt consequuntur vel voluptatem ipsum deleniti impedit repudiandae illo saepe quasi?</p>
	</article>
</div>
!

CSS 

              
                body {
	min-height: 100vh;
	margin: 0;
}

article {
	padding: 5em;
}

.body {
	display: flex;
	flex-direction: column;
	width: 100%;
	height: 100%;
	min-height: 100vh;
	background: rgb(255, 255, 255);
	background-color: var(--bg-color, #fff);
	color: var(--color, #000);
	transition: 250ms;
}

#switcher {
	position: absolute;
	appearance: none;
	top: 1rem;
	right: 1rem;
	width: 4em;
	height: 2em;
	background-color: var(--color, #000);
	border-radius: 2em;
	font-size: 20px;

	&::after {
		position: absolute;
		top: 0.25em;
		left: 0.25em;
		width: 1.5em;
		height: 1.5em;
		content: "";
		background-color: var(--bg-color, #fff);
		border-radius: 2em;
		transform: translateX(var(--translate, 0));
		transition: 250ms;
	}

	&:checked {
		--translate: 2em;
		--bg-color: #424242;
		--color: #81d4fa;

		& ~ * {
			--bg-color: #424242;
			--color: #81d4fa;
		}
	}
}
!

JS
!
999px

Console