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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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About the <head>

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!
Insecure Resource

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CSS

About CSS Preprocessors

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

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Babel includes JSX processing.

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Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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HTML 

              
                <article class="post">
	<h1>This is title</h1>
	<p>Lorem ipsum dolor, sit amet consectetur adipisicing elit. Mollitia corrupti voluptatum ipsa officia. Ducimus debitis a numquam ipsa minus, saepe, expedita, labore deleniti excepturi consectetur quasi deserunt rerum quibusdam perferendis?
	dio eligendi iure perferendis tenetur velit nemo voluptatem amet excepturi, aspernatur delectus veniam possimus eveniet deleniti laboriosam reprehenderit similique nesciunt, dignissimos rem optio veritatis, ipsam illo earum? Quia, debitis.
	Delectus magnam suscipit totam dolorum, molestiae sequi velit, eius quos quo reiciendis harum recusandae dolores omnis a debitis obcaecati sapiente id earum nemo consequuntur, porro neque libero aspernatur! Ullam, dolore.</p>
	<img src="https://fillmurray.com/1020/400" alt="" class="full-width">
	<p>Lorem ipsum dolor, sit amet consectetur adipisicing elit. Mollitia corrupti voluptatum ipsa officia. Ducimus debitis a numquam ipsa minus, saepe, expedita, labore deleniti excepturi consectetur quasi deserunt rerum quibusdam perferendis?
	Sequi architecto mollitia voluptatum quam ab, consectetur cupiditate incidunt. Similique ad nemo commodi nam, dignissimos modi nihil quas deserunt voluptatibus adipisci numquam iure accusantium molestias placeat? Unde sunt libero laboriosam?
	Impedit praesentium aspernatur sed, architecto quia cupiditate. Omnis dolorem dicta explicabo aliquid deleniti amet eveniet totam nemo quisquam, minus atque, soluta ad, laudantium iusto officiis maxime pariatur molestiae? Laudantium, tempora?
	Quaerat vero, culpa architecto maxime quia esse recusandae illo officiis qui in eum minima iusto, corrupti nam at rerum dolorum amet ipsa quibusdam itaque. Placeat sequi totam qui facere earum.
	Impedit maxime unde tempora maiores illum vel corporis porro omnis optio fugit reiciendis asperiores consequatur expedita possimus quis provident quam quisquam molestiae sequi, quae eos. Perspiciatis libero nam ut sapiente!
	Quia blanditiis distinctio sunt quidem ipsum officiis, veritatis sapiente dignissimos voluptatem in inventore obcaecati magnam eos, repudiandae mollitia ad sed incidunt totam illum quos fugit, sit delectus quaerat architecto? Suscipit?
	Repellat at similique nostrum vero ipsum culpa modi quasi saepe quos molestiae recusandae architecto perferendis aut illo quia alias, fugit voluptas! Repellat asperiores itaque corrupti, velit fuga fugiat ratione atque.
	Placeat quos laborum ad, quod vitae consectetur blanditiis tempora, nesciunt tenetur ullam atque sunt accusamus inventore voluptates repellendus dolorem voluptas, sit ipsam? Dolorem quibusdam ipsa, deleniti adipisci repellat veritatis! Ipsum.
	Facilis odio eligendi iure perferendis tenetur velit nemo voluptatem amet excepturi, aspernatur delectus veniam possimus eveniet deleniti laboriosam reprehenderit similique nesciunt, dignissimos rem optio veritatis, ipsam illo earum? Quia, debitis.
	Delectus magnam suscipit totam dolorum, molestiae sequi velit, eius quos quo reiciendis harum recusandae dolores omnis a debitis obcaecati sapiente id earum nemo consequuntur, porro neque libero aspernatur! Ullam, dolore.</p>
</article>
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CSS 

              
                // Post container width
$post-container-width: 32rem;

.post {
	margin: 0 auto;
	max-width: $post-container-width;
	h1 {
		text-align: center;
	}
	p {
		line-height: 1.5;
	}
	.full-width {
		width: 100vw;
		position: relative;
		left: calc(-50vw + (#{$post-container-width} / 2));
		@media(max-width: $post-container-width) {
			left: 0;
		}
	}
}
!

JS
!
999px

Console