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CSS

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JavaScript

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HTML 

              
                <h1>All CSS Accordion</h1>
<div class="accordion">
        <!-- span to target fix closing accordion -->
        <span class="target-fix" id="accordion"></span>
         
        <!-- First Accoridon Option -->
        <div>
            <!-- span to target fix accordion -->
            <span class="target-fix" id="accordion1"></span>
            
            <!-- Link to open accordion, hidden when open --> 
            <a href="#accordion1" id="open-accordion1" title="open">First Accordion</a>
            
            <!-- Link to close accordion, hidden when closed -->
            <a href="#accordion" id="close-accordion1" title="close">First Accordion</a> 
            
            <!-- Accorion content goes in this div -->
            <div class="accordion-content">
                <p>Accordion 1 Content</p>
            </div>
        </div>

        <!-- Second Accoridon Option -->
        <div>
            <span class="target-fix" id="accordion2"></span>
            <a href="#accordion2" id="open-accordion2" title="open">Second Accordion</a>
            <a href="#accordion" id="close-accordion2" title="close">Second Accordion</a>
            <div class="accordion-content">
                <p>Accordion 2 Content.</p>       
            </div>
        </div>

        <!-- Third Accoridon Option -->
        <div>
            <span class="target-fix" id="accordion3"></span>
            <a href="#accordion3" id="open-accordion3" title="open">Third Accordion</a>
            <a href="#accordion" id="close-accordion3" title="close">Third Accordion</a>
            <div class="accordion-content">
                <p>Accordion 3 Content</p>
            </div>
        </div>
    </div>

<div class="readme">
  <p>For multiple accordions on a single page, repeat process, but assign different id names. 
  <a href="https://codepen.io/pollardld/full/lthAF"> Multiple accordions example</a></p>
  
  <p>Beware use on Android 2.2 and 2.3. The default browser on these versions does some curious things.</p>
</div>
!

CSS 

              
                body {
  background: #734f79;
  font-family: 'Flamenco', serif;
}

h1 {
  color: #fff;
  font-weight: normal;
  font-size: 2.5rem;
  text-align: center;
}

.readme {
  color: #fff;
  margin: 0 auto;
  width: 80%;
  
  a {
    color: #00a486;
  }
}

/*_________________  Accordion
________________________________________*/
.accordion {
  position: relative;
  margin: 60px auto;
  width: 80%;
}

[id*="open-accordion"], [id*="close-accordion"] {
  background: #00a486;
  border-bottom: 1px solid #fff;
  line-height: 40px;
  height: 40px;
  display: block;
  margin: 0 auto;
  position: relative;
  width: 99%;
}

[id*="close-accordion"] {
  display: none;
}

.accordion a {
  color: #fff;
  font-size: 1.25em;
  font-weight: normal;
  padding-left: 2%;
  text-decoration: none;
  text-shadow: none;
}

[id*="open-accordion"]:after, [id*="close-accordion"]:after {
  content: "";
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-top: 10px solid rgba(255, 255, 255, 0.6);
  position: absolute;
  right: 5px;
  top: 15px;
  z-index: 999;
  transform: rotate(-90deg);
  -webkit-transform: rotate(-90deg);
}

.target-fix {
  display: block;
  top: 0;
  left: 0;
  position: fixed;
}

.accordion-content {
  background: #fff;
  height: 0;
  margin: -1px auto 0;
  padding: 0 2.5%;
  position: relative;
  overflow: hidden;
  width: 90%;
  transition: all 0.1s ease;
  -webkit-transition: all 0.1s ease;
  -moz-transition: all 0.1s ease;
}

.accordion span:target ~ .accordion-content {
  display: block;
  height: auto;
  padding-bottom: 25px;
  padding-top: 10px;
}

.accordion span:target ~ [id*="close-accordion"] {
  display: block;
}

.accordion span:target ~ [id*="open-accordion"] {
  display: none;
}

.accordion span:target ~ [id*="close-accordion"]:after {
  border-top: 10px solid #333;
  transform: rotate(0deg);
  -webkit-transform: rotate(0deg);
}
!

JS
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