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HTML

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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.

Vendor Prefixing

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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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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 

              
                <div class="slanted">
	<h1>Simple slanted corner</h1>
	<p>Transparent border trick applied on absolutely positioned <code>:after</code> underlying its container which has <code>overflow: hidden</code> to clip out unwanted remainings.</p>
  <p>Slanted bottom part is in fact border-top of <code>:after</code> element with <code>transparent</code> right border.</p>
	<p>Upper rest of container is underlayed with <code>:before</code> which has normal <code>background-color</code> stretched with <code>top/right/bottom/left</code>.</p>
  <p></p>
</div>
!

CSS 

              
                .slanted {
	position: relative;
	width: 500px;
	padding: 0px 50px 30px 50px;
	overflow: hidden;
/*
  in fact, overflow: hidden is not necessary;
  border: 1px solid transparent;  could fix inner margins as well,
  but to prevent rounding errors it seems better to enlarge borders,
  offset them away and crop with overflow
*/
}

.slanted::before ,
.slanted::after {
	content: '';
	position: absolute;
	left: 0; 
	z-index: -1; /* = beneath content */
	background-color: #6f9;
	border-color: #6f9;
}
.slanted::before {
	top: 0;
	right: 0; 
	bottom: 100px; /* = border-top-width of ::after */
}
.slanted:after { 
	top: auto; 
	right: -5px; /* + some px to mask pixel rounding "crack" that could possibly occur while zoomed */
	bottom: 0;
	border-style: solid;
	border-width: 105px 105px 0 0; /* this is the actual slanted bottom "block" */
	background-color: transparent;
	border-right-color: transparent; /* this is the "notch" */
}

body {
	background-image: url('data:image/gif;base64,R0lGODlhBAAEAIAAAAAAAERERCH5BAAAAAAALAAAAAAEAAQAAAIGDB5pYBoFADs=');
	font-family: Georgia, serif;
}
!

JS
!
999px

Console