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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.

Vendor Prefixing

About Vendor Prefixing

To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.

We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).

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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 

              
                <div class="container">
		<nav class="menu">
			<ul>
				<input type="radio" name="menu" id="archive" checked>
				<li>
					<label for="archive" class="title"><i class="fa fa-folder"></i>Archive</label>
					<a href="#">New File</a>
					<a href="#">Open File</a>
					<a href="#">Save As...</a>
					<a href="#">Exit</a>
				</li>
				<input type="radio" name="menu" id="edit">
				<li>
					<label for="edit" class="title"><i class="fa fa-edit"></i>Edit</label>
					<a href="#">Copy</a>
					<a href="#">Cut</a>
					<a href="#">Paste</a>
					<a href="#">Undo</a>
				</li>
				<input type="radio" name="menu" id="tools">
				<li>
					<label for="tools" class="title"><i class="fa fa-gavel"></i>Tools</label>
					<a href="#">Build</a>
					<a href="#">Macros</a>
					<a href="#">Command</a>
					<a href="#">Snippets</a>
				</li>
				<input type="radio" name="menu" id="preferences">
				<li>
					<label for="preferences" class="title"><i class="fa fa-gears"></i>Preferences</label>
					<a href="#">Browser</a>
					<a href="#">Settings</a>
					<a href="#">Packages</a>
					<a href="#">Theme</a>
				</li>
			</ul>
		</nav>
		<main class="main">
			<h1>This is a vertical accordion menu only HTML and CSS</h1>
			<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Voluptatum itaque quae eos natus est asperiores consectetur sit, deserunt saepe totam tenetur numquam dicta harum distinctio accusamus, sed minima reiciendis expedita in. Sint, numquam recusandae id repellendus delectus porro, ipsa a harum obcaecati blanditiis cum accusantium optio voluptate dicta voluptatum. Ipsa nobis aliquid accusantium illum aliquam impedit! Sunt est aliquid ipsam sequi vel repudiandae minima alias earum facere nisi nostrum voluptatum tenetur, iusto illo harum aliquam reprehenderit porro molestias quas possimus voluptatem, doloribus, maiores ea ullam. Sint accusamus vel adipisci delectus nesciunt inventore, exercitationem saepe nulla, dignissimos cum amet consectetur odit voluptas. Laudantium corrupti modi laboriosam aspernatur sed veniam alias hic distinctio, fuga ullam incidunt blanditiis magnam recusandae numquam neque amet enim ratione! Qui numquam obcaecati quas nobis neque. Magni, autem, optio. Esse iste aut quam corrupti qui laboriosam molestias quisquam totam, non consequuntur mollitia maiores itaque et amet nisi voluptatem voluptatum sed dolorem, expedita nam aliquam. Voluptatum quisquam odio ea ullam esse exercitationem ipsum recusandae. Numquam recusandae ex ullam at nobis soluta voluptatum! Ipsum et, ipsam explicabo! Aliquid beatae commodi sint voluptatibus laborum facilis vitae, quaerat, suscipit dolore deserunt alias totam eaque blanditiis rerum, dolor voluptates itaque perferendis repudiandae similique?</p>
			<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Voluptatum itaque quae eos natus est asperiores consectetur sit, deserunt saepe totam tenetur numquam dicta harum distinctio accusamus, sed minima reiciendis expedita in. Sint, numquam recusandae id repellendus delectus porro, ipsa a harum obcaecati blanditiis cum accusantium optio voluptate dicta voluptatum. Ipsa nobis aliquid accusantium illum aliquam impedit! Sunt est aliquid ipsam sequi vel repudiandae minima alias earum facere nisi nostrum voluptatum tenetur, iusto illo harum aliquam reprehenderit porro molestias quas possimus voluptatem, doloribus, maiores ea ullam. Sint accusamus vel adipisci delectus nesciunt inventore, exercitationem saepe nulla, dignissimos cum amet consectetur odit voluptas. Laudantium corrupti modi laboriosam aspernatur sed veniam alias hic distinctio, fuga ullam incidunt blanditiis magnam recusandae numquam neque amet enim ratione! Qui numquam obcaecati quas nobis neque. Magni, autem, optio. Esse iste aut quam corrupti qui laboriosam molestias quisquam totam, non consequuntur mollitia maiores itaque et amet nisi voluptatem voluptatum sed dolorem, expedita nam aliquam. Voluptatum quisquam odio ea ullam esse exercitationem ipsum recusandae. Numquam recusandae ex ullam at nobis soluta voluptatum! Ipsum et, ipsam explicabo! Aliquid beatae commodi sint voluptatibus laborum facilis vitae, quaerat, suscipit dolore deserunt alias totam eaque blanditiis rerum, dolor voluptates itaque perferendis repudiandae similique?</p>
			<p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Voluptatum itaque quae eos natus est asperiores consectetur sit, deserunt saepe totam tenetur numquam dicta harum distinctio accusamus, sed minima reiciendis expedita in. Sint, numquam recusandae id repellendus delectus porro, ipsa a harum obcaecati blanditiis cum accusantium optio voluptate dicta voluptatum. Ipsa nobis aliquid accusantium illum aliquam impedit! Sunt est aliquid ipsam sequi vel repudiandae minima alias earum facere nisi nostrum voluptatum tenetur, iusto illo harum aliquam reprehenderit porro molestias quas possimus voluptatem, doloribus, maiores ea ullam. Sint accusamus vel adipisci delectus nesciunt inventore, exercitationem saepe nulla, dignissimos cum amet consectetur odit voluptas. Laudantium corrupti modi laboriosam aspernatur sed veniam alias hic distinctio, fuga ullam incidunt blanditiis magnam recusandae numquam neque amet enim ratione! Qui numquam obcaecati quas nobis neque. Magni, autem, optio. Esse iste aut quam corrupti qui laboriosam molestias quisquam totam, non consequuntur mollitia maiores itaque et amet nisi voluptatem voluptatum sed dolorem, expedita nam aliquam. Voluptatum quisquam odio ea ullam esse exercitationem ipsum recusandae. Numquam recusandae ex ullam at nobis soluta voluptatum! Ipsum et, ipsam explicabo! Aliquid beatae commodi sint voluptatibus laborum facilis vitae, quaerat, suscipit dolore deserunt alias totam eaque blanditiis rerum, dolor voluptates itaque perferendis repudiandae similique?</p>
		</main>
	</div>
!

CSS 

              
                @import url(https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css);
@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700|Open+Sans:400,300);

* {
	margin: 0;
	padding: 0;
	box-sizing: border-box;
}
body {
	font-family: 'Montserrat', sans-serif;
}
.container {
	width: 100%;
	height: 100%;
}
nav {
	position: fixed;
	display: flex;
	align-items: flex-start;
	width: 20%;
	height: 100%;
	background-color: #111;
}
main {
	position: fixed;
	right: 0;
	width: 80%;
	height: 100%;
	background-color: #fff;
	overflow: auto;
	padding: 40px;
}
h1 {
	font-weight: bold;
	margin-bottom: 50px;
	font-size: 55px;
	text-align: center;
}
p {
	margin-bottom: 20px;
	line-height: 26px;
}
p::first-letter {
	font-size: 200%;
	font-weight: bold;
}
li, ul label.title, ul, a {
	width: 100%;
	color: #FFF;
	font-family: 'Montserrat', 'Open Sans', sans-serif;
	display: block;
	font-weight: bold;
}
ul label {
	height: 35px;
}
ul li{
	height: 35px;
	overflow: hidden;
	transition: all .3s;
}
li {
	display: block;
	background-color: #363636;
}
label.title {
	font-size: 14px;
	background: linear-gradient(#111, #2f2f2f);
	padding: 10px 15px;
	cursor: pointer;
  transition: all .25s;
}
a{
	font-size: 12px;
	text-decoration: none;
	color: #FFF;
	display: block;
	padding: 10px 25px;
	transition: all .25s;
}
a:hover {
	background-color: #444;
  box-shadow: inset 5px 0px 0px 0px #fff;
}
label:hover {
	text-shadow: 0px 0px 10px #fff;
}
input[type="radio"] {
	display: none;
}
#edit:checked + li, #archive:checked + li, #tools:checked + li, #preferences:checked + li {
	height: 179px;
}
i {
	margin-right: 12px;
}
@media screen and (max-width: 600px){
	nav {
		width: 100%;
		position: relative;
	}
	main {
		width: 100%;
		position: relative;
	}
}
!

JS
!
999px

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