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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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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-.

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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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HTML 

              
                <h1>CSS Color Definition Types</h1>

<p>These are only the most common formats for defining color values. You many encounter others.</p>

<section>

	<h2>Hexadecimal / Hex Shorthand</h2>

	<p>The Hex format consists of six digits of alphanumeric code and are denoted by a preceding hashtag, like this: <code>#3ab13f</code>. These values can be easily copy-pasted from most design software.</p>

	<p>For certain colors with repeating digits in the hex code, you can use a three-digit shorthand, like this: <code>#333</code>.</p>

</section>

<section>

	<h2>RGB / RGBA</h2>

	<p><strong>The RGB format</strong> consists of defined values for each of the red, green, and blue colors. It is written like this: <code>rgb( 13, 124, 0 )</code>.</p>

	<p><strong>The RGBA format:</strong>When necessary, you can use a fourth value that denotes opacity to make the color semi-transparent. Opacity is scaled from 0–1, where 0 is completely transparent and 1 is fully opaque. An opacity of .5 is half-transparent. This is written like this: <code>rgba( 13, 124, 0, .5 )</code>. It can also be written with the letter a to denote the use of opacity: <code>rgba( 13, 124, 0, .5 )</code>.</p>

</section>
	
<section>

	<h2>Named Colors</h2>

	<p>For ease of use, there are 147 colors that have human-friendly names. These include common color names like: <code>white</code>, <code>black</code>, <code>red</code>, <code>blue</code>, etc., as well as some fancier ones like <code>cornflowerblue</code> or <code>darkolivegreen</code>.</p>

	<p>There are <a href="https://htmlcolorcodes.com/color-names/" title="Named Color Reference">many websites</a> that list all named CSS colors for reference.</p>

</section>
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CSS 

              
                /* ==========================================================================
   Type
   ========================================================================== */

html {
	line-height: 1.4;
}

h3 {
	margin-top: 3rem;
}

ul{
	padding-left: 1.2rem;
}

li {
	margin-bottom: .5rem;
}

a {
	color: cornflowerblue;
	text-decoration: none;
}

a:hover, a:active, a:focus {
	border-bottom: 1px solid cornflowerblue;
}

.callout {
	font-size: 1.33rem;
}

/* ==========================================================================
   Page Layout
   ========================================================================== */

body {
	margin: 4rem auto;
	max-width: 35rem;
	scroll-behavior: smooth;
}

section {
	border-top: 1px solid #ccc;
	margin-top: 4rem;
	padding-top: 2rem;
}

/* ==========================================================================
   Code Examples
   ========================================================================== */

p > code,
li > code {
	background-color: #f5f2f0;
	color: #905;
	display: inline-block;
	margin: 0 .2rem;
	padding: .15rem .25rem;
}

pre[class*=language-]{
	margin-bottom: 3rem;
}

.bad {
	color: firebrick;
}

.code-example-bad {
	border-left: 3px solid firebrick;
}

.good {
	color: rgb(102, 153, 0);
}

.code-example-good {
	border-left: 3px solid rgb(102, 153, 0);
}

.rendered-example {
  background-color: ghostwhite;
  padding: .75rem;
}

.code-example-good + .rendered-example,
.code-example-good + .rendered-example {
	margin-top: -2rem;
}
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JS
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999px

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