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HTML 

              
                <html>

<head>
  <!-- HTML HEAD CONTENT -->
</head>

<body>
  <header></header>
  <main>
    <!-- 
      You can adjust the behaviour of the accordion here with a true or false value on data-individual-openable 

      data-speed is the amount of miliseconds one entry takes to open and close 
    -->
    <div class="c-accordion" data-individual-openable="false" data-speed="400">
      <div class="c-accordion__entries">

        <div class="c-accordion__entry is-expanded" aria-expanded="true" role="tablist">
          <div id="c-accordion__entry-title-1" class="c-accordion__entry-title" aria-selected="true" aria-controls="c-accordion__entry-body-1" role="tab">
            <a href="" class="c-accordion__entry-header-link js-accordion__entry-header-link">
                 Title
                 <div class="c-accordion__entry-header-icon-wrapper">
                   <svg class="c-accordion__entry-header-icon" xmlns="http://www.w3.org/2000/svg" width="19.999" height="12.979" viewBox="0 0 19.999 12.979">
                    <path d="M12,14.979l-10-10L4.979,2,12,9.021,19.02,2,22,4.979Z" transform="translate(-2 -2)" fill="#7c7c7c"></path>
                  </svg>
                </div>
              </a>
          </div>
          <div id="c-accordion__entry-body-1" class="c-accordion__entry-body" aria-hidden="false" role="tabpanel" aria-labelledby="c-accordion__entry-title-1" style="display: block;">
            <div class="c-accordion__entry-contents c-wysiwyg">Text</div>
          </div>
        </div>
        <div class="c-accordion__entry" aria-expanded="false" role="tablist">
          <div id="c-accordion__entry-title-2" class="c-accordion__entry-title" aria-selected="false" aria-controls="c-accordion__entry-body-2" role="tab">
            <a href="" class="c-accordion__entry-header-link js-accordion__entry-header-link">
                 Title
                 <div class="c-accordion__entry-header-icon-wrapper">
                   <svg class="c-accordion__entry-header-icon" xmlns="http://www.w3.org/2000/svg" width="19.999" height="12.979" viewBox="0 0 19.999 12.979">
                    <path d="M12,14.979l-10-10L4.979,2,12,9.021,19.02,2,22,4.979Z" transform="translate(-2 -2)" fill="#7c7c7c"></path>
                  </svg>
                </div>
              </a>
          </div>
          <div id="c-accordion__entry-body-2" class="c-accordion__entry-body" aria-hidden="true" role="tabpanel" aria-labelledby="c-accordion__entry-title-2">
            <div class="c-accordion__entry-contents c-wysiwyg">Text</div>
          </div>
        </div>
        <div class="c-accordion__entry" aria-expanded="false" role="tablist">
          <div id="c-accordion__entry-title-3" class="c-accordion__entry-title" aria-selected="false" aria-controls="c-accordion__entry-body-3" role="tab">
            <a href="" class="c-accordion__entry-header-link js-accordion__entry-header-link">
                 Title
                 <div class="c-accordion__entry-header-icon-wrapper">
                   <svg class="c-accordion__entry-header-icon" xmlns="http://www.w3.org/2000/svg" width="19.999" height="12.979" viewBox="0 0 19.999 12.979">
                    <path d="M12,14.979l-10-10L4.979,2,12,9.021,19.02,2,22,4.979Z" transform="translate(-2 -2)" fill="#7c7c7c"></path>
                  </svg>
                </div>
              </a>
          </div>
          <div id="c-accordion__entry-body-3" class="c-accordion__entry-body" aria-hidden="true" role="tabpanel" aria-labelledby="c-accordion__entry-title-3">
            <div class="c-accordion__entry-contents c-wysiwyg">Text</div>
          </div>
        </div>
        <div class="c-accordion__entry" aria-expanded="false" role="tablist">
          <div id="c-accordion__entry-title-4" class="c-accordion__entry-title" aria-selected="false" aria-controls="c-accordion__entry-body-4" role="tab">
            <a href="" class="c-accordion__entry-header-link js-accordion__entry-header-link">
                 Title
                 <div class="c-accordion__entry-header-icon-wrapper">
                   <svg class="c-accordion__entry-header-icon" xmlns="http://www.w3.org/2000/svg" width="19.999" height="12.979" viewBox="0 0 19.999 12.979">
                    <path d="M12,14.979l-10-10L4.979,2,12,9.021,19.02,2,22,4.979Z" transform="translate(-2 -2)" fill="#7c7c7c"></path>
                  </svg>
                </div>
              </a>
          </div>
          <div id="c-accordion__entry-body-4" class="c-accordion__entry-body" aria-hidden="true" role="tabpanel" aria-labelledby="c-accordion__entry-title-4">
            <div class="c-accordion__entry-contents c-wysiwyg">Text</div>
          </div>
        </div>

        <!--
          One accordion entry can be initially opened 
          with the following adjustments:

          1) Add class "is-expanded" to .c-accordion__entry
          2) Change aria-expanded value to true on .c-accordion__entry
          3) Change aria-selected value to true on .c-accordion__entry-title
          4) Change aria-hidden value to false on .c-accordion__entry-body
          5) Add style="display:block;" to .c-accordion__entry-body

          Following data needs to be incremented with a unique ID for each accordion entry:

          1) The ID for each .c-accordion__entry-title
          2) The same ID has to be set in the aria-labelledby attribute for the corresponding .c-accordion__entry-body
          3) The ID for each .c-accordion__entry-body
          4) The same ID has to be set in the aria-controls attribute for the corresponding .c-accordion__entry-title
        -->
      </div>
    </div>
  </main>
  <footer></footer>
</body>

</html>
!

CSS 

              
                .c-accordion__entry {
  border-bottom: 1px solid grey;
}

.c-accordion__entry-title {
  position: relative;
}

.c-accordion__entry-header-link {
  display: block;
  padding: 10px 45px 10px 0;
  color: #000;
  font-size: 1.75em;
  cursor: pointer;
}

.c-accordion__entry-body {
  display: none;
}

.c-accordion__entry-contents {
  padding: 5px 0; 
  font-size: 1.125em;
}

.c-accordion__entry-header-icon-wrapper {
  position: absolute;
  top: 50%;
  right: 10px;
  display: block;
  transform: translate(0,-50%);
  transition: all .4s;
}

.c-accordion__entry-header-icon {
  display: block;
}


// This needs to be so specific because then we can nest accordions
.c-accordion__entry.is-expanded > .c-accordion__entry-title > .c-accordion__entry-header-link > .c-accordion__entry-header-icon-wrapper {
  transform: translate(0,-50%) rotate(180deg);
}

// ===== ADDITIONAL STYLING FOR CODEPEN =====

main {
  max-width: 1000px;
  margin: 25px auto;
}
!

JS 

              
                var MODULE = MODULE || {};

(function($, MODULE) {
  MODULE.init_accordion = function() {
    // Logic for accordion
    var accordion = (function() {
      var $accordion_elem = $(".c-accordion"),
        $accordion_headerlink = $accordion_elem.find(
          ".js-accordion__entry-header-link"
        ),
        $accordion_item = $accordion_elem.find(".c-accordion__entry");

      var settings = {
        speed: parseInt($accordion_elem.attr("data-speed")) || 400,
        individual_openable: $accordion_elem.attr("data-individual-openable") === "true"
      };

      return {
        init: function() {
          $accordion_headerlink.on("click", function(e) {
            e.preventDefault();
            accordion.toggle($(this));
          });

          if (
            !settings.individual_openable &&
            $(".c-accordion__entry.is-expanded").length > 1
          ) {
            $(".c-accordion__entry.is-expanded").removeClass(
              "is-expanded"
            );
          }
        },
        toggle: function(self) {
          if (
            !settings.individual_openable &&
            self[0] !=
              self
                .closest(".c-accordion")
                .find(
                  ".c-accordion__entry.is-expanded .c-accordion__entry-header-link"
                )[0]
          ) {
            self
              .closest(".c-accordion")
              .find(".c-accordion__entry")
              .removeClass("is-expanded")
              .find(".c-accordion__entry-body")
              .slideUp();
          }

          self
            .closest(".c-accordion__entry")
            .toggleClass("is-expanded")
            .attr("aria-expanded", function(i, attr) {
              return attr == "true" ? "false" : "true";
            });

          self.parent().attr("aria-selected", function(i, attr) {
            return attr == "true" ? "false" : "true";
          });

          self
            .parent()
            .next()
            .stop()
            .slideToggle(settings.speed)
            .attr("aria-hidden", function(i, attr) {
              return attr == "true" ? "false" : "true";
            });
        }
      };
    })();

    accordion.init();
  };

  /* READY FUNCTION
  ====================== */

  $(function() {
    MODULE.init_accordion();
  });
})(jQuery, MODULE);
!
999px

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