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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>

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. If you need things in the <head> of the document, put that code here.

!
Insecure Resource

The resource you are linking to is using the 'http' protocol, which may not work when the browser is using https.

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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You can apply CSS to your Pen from any stylesheet on the web. Just put a URL to it here and we'll apply it, in the order you have them, before the CSS in the Pen itself.

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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 

              
                <h1>Link Ideas (proof of concept)</h1>
<div class="wrapper">
  <a class="first after" href="#">Left to Right</a>
</div>
<div class="wrapper">
  <a class="second after" href="#">Right to Left</a>
</div>
<div class="wrapper">
  <a class="third after" href="#">Start Centered</a>
</div>
<div class="wrapper">
  <a class="fourth before after" href="#">Top & Bottom // Left to Right</a>
</div>
<div class="wrapper">
  <a class="fifth before after" href="#">Top & Bottom // Right to Left</a>
</div>
<div class="wrapper">
  <a class="sixth before after" href="#">Top & Bottom // Start Centered</a>
</div>
<div class="wrapper">
  <a class="seventh before after" href="#">Top & Bottom // Opposite Start</a>
</div>
<div class="wrapper">
  <a class="eigth before after" href="#">Top & Bottom // Opposite Start Reversed</a>
</div>
<div class="wrapper">
  <span class="square individual">
    <a class="ninth before after" href="#">Cool Square</a>
  </span>
</div>
<div class="wrapper">
  <span class="square">
    <a class="tenth before after" href="#">Cool Square Simultaneous</a>
  </span>
</div>
!

CSS 

              
                @import url(https://fonts.googleapis.com/css?family=Open+Sans);

body{
  font-family:'Open Sans', sans-serif;
  background:#151837;
  width:90%;
  margin:0 auto;
  padding:2em 0 6em;
}
h1:before{
  content: "// ";
}
h1{
  font-size:3em;
  color:#fefefe;
  text-transform:lowercase;
}
.wrapper{
  margin:3em 0;
}
a,a:visited,a:hover,a:active{
  -webkit-backface-visibility:hidden;
          backface-visibility:hidden;
	position:relative;
  transition:0.5s color ease;
	text-decoration:none;
	color:#81b3d2;
	font-size:2.5em;
}
a:hover{
	color:#d73444;
}
a.before:before,a.after:after{
  content: "";
  transition:0.5s all ease;
  -webkit-backface-visibility:hidden;
          backface-visibility:hidden;
  position:absolute;
}
a.before:before{
  top:-0.25em;
}
a.after:after{
  bottom:-0.25em;
}
a.before:before,a.after:after{
  height:5px;
  height:0.35rem;
  width:0;
  background:#d73444;
}
a.first:after{
  left:0;
}
a.second:after{
  right:0;
}
a.third:after,a.sixth:before,a.sixth:after{
  left:50%;
  -webkit-transform:translateX(-50%);
          transform:translateX(-50%);
}
a.fourth:before,a.fourth:after{
  left:0;
}
a.fifth:before,a.fifth:after{
  right:0;
}
a.seventh:before{
  right:0;
}
a.seventh:after{
  left:0;
}
a.eigth:before{
  left:0;
}
a.eigth:after{
  right:0;
}
a.before:hover:before,a.after:hover:after{
  width:100%;
}
.square{
  box-sizing:border-box;
  margin-left:-0.4em;
  position:relative;
  font-size:2.5em;
  overflow:hidden;
}
.square a{
  position:static;
  font-size:100%;
  padding:0.2em 0.4em;
}
.square:before,.square:after{
  content: "";
  box-sizing:border-box;
  transition:0.25s all ease;
  -webkit-backface-visibility:hidden;
          backface-visibility:hidden;
  position:absolute;
  width:5px;
  width:0.35rem;
  height:0;
  background:#d73444;
}
.square:before{
  left:0;
  bottom:-0.2em;
}
.square.individual:before{
  transition-delay:0.6s;
}
.square:after{
  right:0;
  top:-0.2em;
}
.square.individual:after{
  transition-delay:0.2s;
}
.square a:before{
  left:0;
  transition:0.25s all ease;
}
.square a:after{
  right:0;
  transition:0.25s all ease;
}
.square.individual a:after{
  transition:0.25s all ease 0.4s;
}
.square:hover:before,.square:hover:after{
  height:calc(100% + 0.4em);
}
.square:hover a:before,.square:hover a:after{
  width:100%;
}
!

JS
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999px

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