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                <div class="row">
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    <h1>Toggle a CSS class</h1>
    <p>To setup a class toggle, start by adding the attribute data-toggler to an element. The value of data-toggler is the class you want to toggle. Also give the element a unique ID so it can be targeted.</p>
    <p>Then, add data-toggle to any element, with the ID of the target as the value of the attribute. Now, any time you click on this element, the class will toggle on and off on the target.</p>

    <p><a data-toggle="menuBar">Expand!</a></p>

    <ul class="menu" id="menuBar" data-toggler=".expanded">
      <li><a href="#">One</a></li>
      <li><a href="#">Two</a></li>
      <li><a href="#">Three</a></li>
      <li><a href="#">Four</a></li>