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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.

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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <html lang="en">
  <head>
    <link href="https://fonts.googleapis.com/css?family=Open+Sans" rel="stylesheet">
    <link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
    <link href="https://fonts.googleapis.com/css?family=Lobster+Two" rel="stylesheet">
  </head>

  <body>
    <h1>Accessible Accordion</h1>
        
    <!-- Accordion 1 -->
    <section class="accordion" role="tablist" aria-live="polite" data-behavior="accordion">

      <article class="accordion__item js-show-item-default" data-binding="expand-accordion-item">
        <span id="tab1" tabindex="0" class="accordion__title" aria-controls="panel1" role="tab" aria-selected="false" aria-expanded="false" data-binding="expand-accordion-trigger">
          <h5>Use the tab key to navigate...</h5>
        </span>

        <div id="panel1" class="accordion__content" role="tabpanel" aria-hidden="true" aria-labelledby="tab1" data-binding="expand-accordion-container">
          <div class="accordion__content-inner">
            <p>You can cycle through all the different accordion items through tabbing.</p>
          </div>
        </div>

      </article>

      <article class="accordion__item js-show-item-default" data-binding="expand-accordion-item">
        <span id="tab2" tabindex="0" class="accordion__title" aria-controls="panel2" role="tab" aria-selected="false" aria-expanded="false" data-binding="expand-accordion-trigger">
          <h5>Or, you can use your mouse.</h5>
        </span>

        <div id="panel2" class="accordion__content" role="tabpanel" aria-hidden="true" aria-labelledby="tab2" data-binding="expand-accordion-container">
          <div class="accordion__content-inner">
            <p>This accordion can be used by both mouse and keyboard-only users.</p>
          </div>
        </div>
      </article>
      
      <article class="accordion__item js-show-item-default" data-binding="expand-accordion-item">
        <span id="tab3" tabindex="0" class="accordion__title" aria-controls="panel3" role="tab" aria-selected="false" aria-expanded="false" data-binding="expand-accordion-trigger">
          <h5>Click here to view more</h5>
        </span>

        <div id="panel3" class="accordion__content" role="tabpanel" aria-hidden="true" aria-labelledby="tab3" data-binding="expand-accordion-container">
          <div class="accordion__content-inner">
            <p>You can also use either the space bar or enter key to expand/collapse these panels.</p>
          </div>
        </div>
      </article>
      
      <article class="accordion__item js-show-item-default" data-binding="expand-accordion-item">
        <span id="tab4" tabindex="0" class="accordion__title" aria-controls="panel4" role="tab" aria-selected="false" aria-expanded="false" data-binding="expand-accordion-trigger">
          <h5>ARIA</h5>
        </span>

        <div id="panel4" class="accordion__content" role="tabpanel" aria-hidden="true" aria-labelledby="tab4" data-binding="expand-accordion-container">
          <div class="accordion__content-inner">
            <p>This accordion makes use of ARIA tags which help aid accessibility.</p>
          </div>
        </div>
      </article>

    </section>

    <!-- Accordion 2 -->
    <section class="accordion" role="tablist" aria-live="polite" data-behavior="accordion">
      <article class="accordion__item js-show-item-default" data-binding="expand-accordion-item">
        <span id="tab5" tabindex="0" class="accordion__title" aria-controls="panel5" role="tab" aria-selected="false" aria-expanded="false" data-binding="expand-accordion-trigger">
          <h5>Heading 1</h5>
        </span>

        <div id="panel5" class="accordion__content" role="tabpanel" aria-hidden="true" aria-labelledby="tab5" data-binding="expand-accordion-container">
          <div class="accordion__content-inner">
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.</p>
          </div>
        </div>

      </article>

      <article class="accordion__item js-show-item-default" data-binding="expand-accordion-item">
        <span id="tab6" tabindex="0" class="accordion__title" aria-controls="panel6" role="tab" aria-selected="false" aria-expanded="false" data-binding="expand-accordion-trigger">
          <h5>Heading 2</h5>
        </span>

        <div id="panel6" class="accordion__content" role="tabpanel" aria-hidden="true" aria-labelledby="tab6" data-binding="expand-accordion-container">
          <div class="accordion__content-inner">
            <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam.</p>
          </div>
        </div>
      </article>

    </section>
  </body>
</html>
!

CSS 

              
                body {
  background-color: #F6F7EB;
  font-family: 'Open Sans', sans-serif;
}

h1 {
  font-family: 'Lobster Two', cursive;
  text-align: center;
  margin-top: 30px;
  font-size: 50px;
  color: #2b3a40;
}

.accordion { 
  background-color: #fefffa;
  max-width: 600px;
  margin: 50px auto;
  border-top: 6px solid #44BBA4;
  line-height: 1.6;
  box-shadow: 5px 5px 10px 0px #a4bac1;
  
  &__item {
    border-bottom: 1px solid #dce7eb;
  }

  &__title {
    padding: 15px 15px 15px 40px;
    display: block;
    position: relative;
    font-weight: 400;

    &:before {
      font-family: FontAwesome;
      content: "\f055";
      font-size: 20px;
      position: absolute;
      left: 15px;
      top: 12px;
      color: #44BBA4;
    }
    
    h5 {
      border-bottom: 1px solid #fefffa;
      display:inline-block;
    }

    &:hover,
    &:focus {
      cursor: pointer;
      outline: none;
      h5 {
        border-bottom-color: #a8bdc4;
        display:inline-block;
      }
    }

    .is-expanded & {
      &:before {
        content: "\f056";
      }

    }
  }

    &__content-inner {
        padding: 0 40px 10px 40px;
    }

  &__content {
    transition: height 0.3s ease-out;
    height: 0;
    overflow: hidden;
  }
}
!

JS 

              
                var accordion = $('body').find('[data-behavior="accordion"]');
var expandedClass = 'is-expanded';

$.each(accordion, function () { // loop through all accordions on the page

  var accordionItems = $(this).find('[data-binding="expand-accordion-item"]');

  $.each(accordionItems, function () { // loop through all accordion items of each accordion
    var $this = $(this);
    var triggerBtn = $this.find('[data-binding="expand-accordion-trigger"]');
    
    var setHeight = function (nV) {
      // set height of inner content for smooth animation
      var innerContent = nV.find('.accordion__content-inner')[0],
          maxHeight = $(innerContent).outerHeight(),
          content = nV.find('.accordion__content')[0];

      if (!content.style.height || content.style.height === '0px') {
        $(content).css('height', maxHeight);
      } else {
        $(content).css('height', '0px');
      }
    };
    
    var toggleClasses = function (event) {
      var clickedItem = event.currentTarget;
      var currentItem = $(clickedItem).parent();
      var clickedContent = $(currentItem).find('.accordion__content')
      $(currentItem).toggleClass(expandedClass);
      setHeight(currentItem);
      
      if ($(currentItem).hasClass('is-expanded')) {
        $(clickedItem).attr('aria-selected', 'true');
        $(clickedItem).attr('aria-expanded', 'true');
        $(clickedContent).attr('aria-hidden', 'false');

      } else {
        $(clickedItem).attr('aria-selected', 'false');
        $(clickedItem).attr('aria-expanded', 'false');
        $(clickedContent).attr('aria-hidden', 'true');
      }
    }
    
    triggerBtn.on('click', event, function (e) {
      e.preventDefault();
      toggleClasses(event);
    });

    // open tabs if the spacebar or enter button is clicked whilst they are in focus
    $(triggerBtn).on('keydown', event, function (e) {
      if (e.keyCode === 13 || e.keyCode === 32) {
        e.preventDefault();
        toggleClasses(event);
      }
    });
  });

});
!
999px

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