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<nav class="navbar navbar-default navbar-fixed-top">
  <div class="container">
    <input type="checkbox" id="navbar-toggle-cbox">
    <div class="navbar-header">
      <label for="navbar-toggle-cbox" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
        <span class="sr-only">Toggle navigation</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </label>
      <a class="navbar-brand" href="#">Project name</a>
    </div>
    <div id="navbar" class="navbar-collapse collapse">
      <ul class="nav navbar-nav">
        <li class="active"><a href="#">Home</a></li>
        <li><a href="#about">About</a></li>
      </ul>
    </div>
    <!--/.nav-collapse -->
  </div>
</nav>

#navbar-toggle-cbox:checked ~ .collapse {
    display: block;
}

#navbar-toggle-cbox {
  display:none
}