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HTML

About HTML Preprocessors

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.

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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 

              
                <div class="accordion js-accordion">
  <div class="accordion__item js-accordion-item">
    <div class="accordion-header js-accordion-header">Panel 1</div> 
  <div class="accordion-body js-accordion-body">
    <div class="accordion-body__contents">
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
    </div>
      <div class="accordion js-accordion">
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 1</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 2</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
      </div><!-- end of sub accordion -->
    </div
    </div><!-- end of accordion body -->
  </div><!-- end of accordion item -->
  <div class="accordion__item js-accordion-item active">
    <div class="accordion-header js-accordion-header">Panel 2</div> 
  <div class="accordion-body js-accordion-body">
    <div class="accordion-body__contents">
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
    </div>
      <div class="accordion js-accordion">
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 1</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 2</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
      </div><!-- end of sub accordion -->
    </div><!-- end of accordion body -->
  </div><!-- end of accordion item -->
    <div class="accordion__item js-accordion-item">
    <div class="accordion-header js-accordion-header">Panel 3</div> 
  <div class="accordion-body js-accordion-body">
    <div class="accordion-body__contents">
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
    </div>
      <div class="accordion js-accordion">
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 1</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 2</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
      </div><!-- end of sub accordion -->
    </div><!-- end of accordion body -->
  </div><!-- end of accordion item -->
     <div class="accordion__item js-accordion-item">
    <div class="accordion-header js-accordion-header">Panel 4</div> 
  <div class="accordion-body js-accordion-body">
    <div class="accordion-body__contents">
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
    </div>
      <div class="accordion js-accordion">
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 1</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 2</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
      </div><!-- end of sub accordion -->
    </div><!-- end of accordion body -->
  </div><!-- end of accordion item -->
     <div class="accordion__item js-accordion-item">
    <div class="accordion-header js-accordion-header">Panel 5</div> 
  <div class="accordion-body js-accordion-body">
    <div class="accordion-body__contents">
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
    </div>
      <div class="accordion js-accordion">
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 1</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 2</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
      </div><!-- end of sub accordion -->
    </div><!-- end of accordion body -->
  </div><!-- end of accordion item -->
     <div class="accordion__item js-accordion-item">
    <div class="accordion-header js-accordion-header">Panel 6</div> 
  <div class="accordion-body js-accordion-body">
    <div class="accordion-body__contents">
      Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
    </div>
      <div class="accordion js-accordion">
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 1</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
        <div class="accordion__item js-accordion-item">
           <div class="accordion-header js-accordion-header">Sub Panel 2</div> 
           <div class="accordion-body js-accordion-body">
             <div class="accordion-body__contents">
              Lorem ipsum dolor sit amet consectetur adipisicing elit. Dignissimos sequi placeat distinctio dolor, amet magnam voluptatibus eos ex vero, sunt veritatis esse. Nostrum voluptatum et repudiandae vel sed, explicabo in?
             </div><!-- end of sub accordion item body contents -->
           </div><!-- end of sub accordion item body -->
        </div><!-- end of sub accordion item -->
      </div><!-- end of sub accordion -->
    </div><!-- end of accordion body -->
  </div><!-- end of accordion item -->
</div><!-- end of accordion -->
!

CSS 

              
                body {
  font-size: 62.5%;
  background: #dadada;
  font-family: 'Open Sans', sans-serif;
  line-height: 2;
  padding: 5em;
}

.accordion {
  font-size: 1rem;
  width: 30vw;
  margin: 0 auto;
  border-radius: 5px;
}

.accordion-header,
.accordion-body {
  background: white;
}

.accordion-header {
  padding: 1.5em 1.5em;
  background: #3F51B5;
  color: white;
  cursor: pointer;
  font-size: .7em;
  letter-spacing: .1em;
  transition: all .3s;
  text-transform: uppercase;
}

.accordion__item {
    border-bottom: 1px solid #3a4ba4;
}

.accordion__item .accordion__item {
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.accordion-header:hover {
  background: #2D3D99;
  position: relative;
  z-index: 5;
}

.accordion-body {
  background: #fcfcfc;
  color: #353535;
  display: none;
}

.accordion-body__contents {
  padding: 1.5em 1.5em;
  font-size: .85em;
}

.accordion__item.active:last-child .accordion-header {
  border-radius: none;
}

.accordion:first-child > .accordion__item > .accordion-header {
  border-bottom: 1px solid transparent;
}

.accordion__item > .accordion-header:after {
  content: "\f3d0";
  font-family: IonIcons;
  font-size: 1.2em;
  float: right;
  position: relative;
  top: -2px;
  transition: .3s all;
  transform: rotate(0deg);
}

.accordion__item.active > .accordion-header:after {
  transform: rotate(-180deg);
}

.accordion__item.active .accordion-header {
  background: #2D3D99;
}

.accordion__item .accordion__item .accordion-header {
  background: #f1f1f1;
  color: #353535;
}

@media screen and (max-width: 1000px) {
  body {
    padding: 1em;
  }
  
  .accordion {
    width: 100%;
  }
}
!

JS 

              
                var accordion = (function(){
  
  var $accordion = $('.js-accordion');
  var $accordion_header = $accordion.find('.js-accordion-header');
  var $accordion_item = $('.js-accordion-item');
 
  // default settings 
  var settings = {
    // animation speed
    speed: 400,
    
    // close all other accordion items if true
    oneOpen: false
  };
    
  return {
    // pass configurable object literal
    init: function($settings) {
      $accordion_header.on('click', function() {
        accordion.toggle($(this));
      });
      
      $.extend(settings, $settings); 
      
      // ensure only one accordion is active if oneOpen is true
      if(settings.oneOpen && $('.js-accordion-item.active').length > 1) {
        $('.js-accordion-item.active:not(:first)').removeClass('active');
      }
      
      // reveal the active accordion bodies
      $('.js-accordion-item.active').find('> .js-accordion-body').show();
    },
    toggle: function($this) {
            
      if(settings.oneOpen && $this[0] != $this.closest('.js-accordion').find('> .js-accordion-item.active > .js-accordion-header')[0]) {
        $this.closest('.js-accordion')
               .find('> .js-accordion-item') 
               .removeClass('active')
               .find('.js-accordion-body')
               .slideUp()
      }
      
      // show/hide the clicked accordion item
      $this.closest('.js-accordion-item').toggleClass('active');
      $this.next().stop().slideToggle(settings.speed);
    }
  }
})();

$(document).ready(function(){
  accordion.init({ speed: 300, oneOpen: true });
});
!
999px

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