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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

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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

About 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

Add Packages

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
!
999px

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