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<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="../lib/w3.css">

<body class="w3-container">

<h2>Accordion Width</h2>
<p>Use the CSS width property to change the width of the accordion:</p>

<div class="w3-accordion w3-light-grey w3-section" style="width:25%">
  <button onclick="myFunction('Demo1')" class="w3-btn-block">
  25%</button>
  <div id="Demo1" class="w3-accordion-content w3-container">
    <p>Lorem ipsum 25% width</p>
  </div>
</div>

<div class="w3-accordion w3-light-grey w3-section" style="width:50%">
  <button onclick="myFunction('Demo2')" class="w3-btn-block">
  50%</button>
  <div id="Demo2" class="w3-accordion-content w3-container">
    <p>Lorem ipsum 50% width</p>
  </div>
</div>

<div class="w3-accordion w3-light-grey w3-section" style="width:75%">
  <button onclick="myFunction('Demo3')" class="w3-btn-block">
  75%</button>
  <div id="Demo3" class="w3-accordion-content w3-container">
    <p>Lorem ipsum 75% width</p>
  </div>
</div>

<div class="w3-accordion w3-light-grey w3-section">
  <button onclick="myFunction('Demo4')" class="w3-btn-block">
  Default (100%)</button>
  <div id="Demo4" class="w3-accordion-content w3-container">
    <p>Lorem ipsum 100% width</p>
  </div>
</div>

<script>
function myFunction(id) {
    var x = document.getElementById(id);
    if (x.className.indexOf("w3-show") == -1) {
        x.className += " w3-show";
    } else { 
        x.className = x.className.replace(" w3-show", "");
    }
}
</script>

</body>
</html>