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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

In CodePen, whatever you write in the HTML editor is what goes within the <body> tags in a basic HTML5 template. So you don't have access to higher-up elements like the <html> tag. If you want to add classes there that can affect the whole document, this is the place to do it.

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

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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 

              
                <ul class="tab-container">
  <li>
    <input class="tab-toggle" id="tab-1" type="radio" name="toggle" checked /> 
    <label data-title="Tab 1" class="tab l-b" for="tab-1">Tab 1</label>            
    <ul class="tab-content-container">
      <li class="tab-content">
        This is a testing text to test the tab content container. Lorem Ipsum dolor sit amet! Consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. 
        This is a testing text to test the tab content container. Lorem Ipsum dolor sit amet! 
        <div class="arrows">
          <label class="back" for="tab-4">&#8249;</label>
          <label class="next" for="tab-2">&#8250;	</label>   
        </div>
      </li>
    </ul>
  </li>
  <li>
    <input class="tab-toggle" id="tab-2" type="radio" name="toggle" />
    <label class="tab" for="tab-2">Tab 2</label> 
    <ul class="tab-content-container">
      <li class="tab-content">
        Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
        Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
        <div class="arrows">
          <label class="back" for="tab-1">&#8249;</label>
          <label class="next" for="tab-3">&#8250;	</label>   
        </div>   
      </li>
    </ul>
  </li>
  <li>
    <input class="tab-toggle" id="tab-3" type="radio" name="toggle"/>        
    <label class="tab" for="tab-3">Tab 3</label> 
    <ul class="tab-content-container">
      <li class="tab-content">
        Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.
        Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.
        <div class="arrows">
          <label class="back" for="tab-2">&#8249;</label>
          <label class="next" for="tab-4">&#8250;	</label>   
        </div>
      </li>
    </ul>    
  </li>
  <li>
    <input class="tab-toggle" id="tab-4" type="radio" name="toggle"/>     
    <label class="tab" for="tab-4">Tab 4</label> 
    <ul class="tab-content-container">
      <li class="tab-content">
        This is the final content for the tab example.
        <div class="arrows">
          <label class="back" for="tab-3">&#8249;</label>
          <label class="next" for="tab-1">&#8250;	</label>   
        </div>
      </li>  
    </ul>  
  </li>
</ul>
!

CSS 

              
                *, *:before, *:after { box-sizing: border-box; }
html { margin: 0; font-family: arial; height: 100vh; background: #ccc; }

.tab-container {
  list-style-type: none;
  padding: 0;
  margin: 60px auto;
  max-width: 350px;
  position: relative;
  background: #fff;
  ul { list-style-type: none; padding: 0; }
  .arrows { 
    display: block;
    width: 60px;
    font-size: 32px;    
    bottom: 10px;
    right: 0px;
    position: absolute;
    label { 
      display: inline-block; 
      cursor: pointer; 
      color: #aaa; 
      -webkit-user-select: none;
      -moz-user-select: none;    
      -ms-user-select: none;     
      user-select: none;  
      margin-left: 5px;      
      &:hover { color: #333; }
    }
  }
  .tab-content-container { 
    border-bottom-left-radius: 4px;
    border-bottom-right-radius: 4px; 
    height: 0; 
    opacity: 0; 
    overflow: hidden; 
    line-height: 22px;
    background: #fff;
    position: absolute;
    top: 42px;
    padding: 0px 40px 0 20px;
    border: 2px solid #446CB3;
    border-top: 0;
    box-shadow: 0 5px 5px -5px #333;  
    .tab-content {
      opacity: 0;
      padding: 15px 0;
      min-height: 185px;  
      transition: opacity 0.1s ease-in;    
    }
  }
  .tab {
    outline: 0;
    float: left;
    cursor: pointer;    
    opacity: 1;
    width: 25%;
    line-height: 40px;
    display: block;
    margin: 0;
    position: relative;
    background: #446CB3;
    color: #fff;
    text-align: center;    
    border-top: 2px solid #446CB3;
    border-right: 2px solid #446CB3;
    &.l-b { border-left: 2px solid #446CB3; }
    &:hover { background: #365690; }          
  }
  .tab-toggle {
    display: none;
    &.active + .tab,
    &:checked + .tab { 
      background: #fff; 
      color: #333; 
    }
    &.active ~ .tab-content-container,
    &:checked ~ .tab-content-container { 
      height: auto;
      opacity: 1;
      .tab-content { 
        opacity: 1; 
        label { opacity: 1; }
      }
    }
  }
}
!

JS 

              
                // Optional jQuery class toggle for added robustness. 

/* 
var labelID;

$('label').click(function() {
  labelID = $(this).attr('for');
  $('input').removeClass('active');
  $('#' + labelID).addClass('active');
}); 
*/
!
999px

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