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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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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 

              
                <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
<figure class="tabBlock">
  <ul class="tabBlock-tabs">
    <li class="tabBlock-tab is-active">Tab 1</li>
    <li class="tabBlock-tab">Tab 2</li>
  </ul>
  <div class="tabBlock-content">
    <div class="tabBlock-pane">
      <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Molestias molestiae atque quis blanditiis eaque maiores ducimus optio neque debitis quos dolorum odit unde quibusdam tenetur quaerat magni eius quod tempore.</p>
    </div>
    <div class="tabBlock-pane">
      <ul>
        <li>Lorem ipsum dolor sit amet.</li>
        <li>Minima mollitia tenetur nesciunt modi?</li>
        <li>Id sint fugit et sapiente.</li>
        <li>Nam deleniti libero obcaecati pariatur.</li>
        <li>Nemo optio iste labore similique?</li>
      </ul>
    </div>
  </div>
</figure>

<figure class="tabBlock">
  <ul class="tabBlock-tabs">
    <li class="tabBlock-tab">Tab 1</li>
    <li class="tabBlock-tab is-active">Tab 2</li>
  </ul>
  <div class="tabBlock-content">
    <div class="tabBlock-pane">
      <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Sint et accusamus cumque soluta iste quasi ad blanditiis expedita minus quos amet neque illo praesentium nostrum asperiores quisquam atque est repudiandae assumenda ipsum repellat ipsa impedit! Ipsum unde sapiente exercitationem tenetur repellendus nemo harum reiciendis ipsam quo iusto esse temporibus itaque.</p>
    </div>
    <div class="tabBlock-pane">
      <ul>
        <li>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Voluptas rem.</li>
        <li>Id atque earum similique repellat nesciunt odio veniam commodi reprehenderit.</li>
        <li>Est placeat voluptatibus id impedit perspiciatis repellat libero sequi rerum?</li>
        <li>Tempora impedit dolorum illum rem fuga voluptas molestias maiores vitae.</li>
        <li>Facilis adipisci vel atque consequuntur mollitia iusto saepe optio placeat.</li>
        <li>Et culpa molestias laboriosam aperiam alias nihil fugit ad illum.</li>
      </ul>
    </div>
  </div>
</figure>
!

CSS 

              
                .group::after, .tabBlock-tabs::after {
  clear: both;
  content: "";
  display: table;
}

*, ::before, ::after {
  box-sizing: border-box;
}

body {
  color: #222;
  font-family: "Source Sans Pro", "Helvetica Neue", "Helvetica", "Arial", sans-serif;
  line-height: 1.5;
  margin: 0 auto;
  max-width: 50rem;
  padding: 2.5rem 1.25rem;
}
@media screen and (min-width: 700px) {
  body {
    font-size: 137.5%;
  }
}

p, ol, ul {
  margin-bottom: 1.25rem;
  margin-top: 0;
}

ol, ul {
  padding: 0;
  margin-left: 1.25rem;
}

.unstyledList, .tabBlock-tabs {
  list-style: none;
  margin: 0;
  padding: 0;
}

.tabBlock {
  margin: 0 0 2.5rem;
}

.tabBlock-tab {
  background-color: #fff;
  border-color: #d8d8d8;
  border-left-style: solid;
  border-top: solid;
  border-width: 2px;
  color: #b5a8c5;
  cursor: pointer;
  display: inline-block;
  font-weight: 600;
  float: left;
  padding: 0.625rem 1.25rem;
  position: relative;
  -webkit-transition: 0.1s ease-in-out;
          transition: 0.1s ease-in-out;
}
.tabBlock-tab:last-of-type {
  border-right-style: solid;
}
.tabBlock-tab::before, .tabBlock-tab::after {
  content: "";
  display: block;
  height: 4px;
  position: absolute;
  -webkit-transition: 0.1s ease-in-out;
          transition: 0.1s ease-in-out;
}
.tabBlock-tab::before {
  background-color: #b5a8c5;
  left: -2px;
  right: -2px;
  top: -2px;
}
.tabBlock-tab::after {
  background-color: transparent;
  bottom: -2px;
  left: 0;
  right: 0;
}
@media screen and (min-width: 700px) {
  .tabBlock-tab {
    padding-left: 2.5rem;
    padding-right: 2.5rem;
  }
}
.tabBlock-tab.is-active {
  position: relative;
  color: #975997;
  z-index: 1;
}
.tabBlock-tab.is-active::before {
  background-color: #975997;
}
.tabBlock-tab.is-active::after {
  background-color: #fff;
}

.tabBlock-content {
  background-color: #fff;
  border: 2px solid #d8d8d8;
  padding: 1.25rem;
}

.tabBlock-pane > :last-child {
  margin-bottom: 0;
}
!

JS 

              
                var TabBlock = {
  s: {
    animLen: 200
  },
  
  init: function() {
    TabBlock.bindUIActions();
    TabBlock.hideInactive();
  },
  
  bindUIActions: function() {
    $('.tabBlock-tabs').on('click', '.tabBlock-tab', function(){
      TabBlock.switchTab($(this));
    });
  },
  
  hideInactive: function() {
    var $tabBlocks = $('.tabBlock');
    
    $tabBlocks.each(function(i) {
      var 
        $tabBlock = $($tabBlocks[i]),
        $panes = $tabBlock.find('.tabBlock-pane'),
        $activeTab = $tabBlock.find('.tabBlock-tab.is-active');
      
      $panes.hide();
      $($panes[$activeTab.index()]).show();
    });
  },
  
  switchTab: function($tab) {
    var $context = $tab.closest('.tabBlock');
    
    if (!$tab.hasClass('is-active')) {
      $tab.siblings().removeClass('is-active');
      $tab.addClass('is-active');
   
      TabBlock.showPane($tab.index(), $context);
    }
   },
  
  showPane: function(i, $context) {
    var $panes = $context.find('.tabBlock-pane');
   
    // Normally I'd frown at using jQuery over CSS animations, but we can't transition between unspecified variable heights, right? If you know a better way, I'd love a read it in the comments or on Twitter @johndjameson
    $panes.slideUp(TabBlock.s.animLen);
    $($panes[i]).slideDown(TabBlock.s.animLen);
  }
};

$(function() {
  TabBlock.init();
});
!
999px

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