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HTML 

              
                <!DOCTYPE html>
<html>

<head>
	<meta charset='UTF-8'>
	
	<title>Custom and Indeterminate Checkboxes</title>
	
	<link rel='stylesheet' href='css/style.css'>

</head>

<body>

	<div id="page-wrap">
	
	   <h2>Treeview with Custom Checkboxes and Indeterminate State</h2>
		
  	 <ul class="treeview">
        <li>
            <input type="checkbox" name="tall" id="tall">
            <label for="tall" class="custom-unchecked">Tall Things</label>
            
            <ul>
                 <li>
                     <input type="checkbox" name="tall-1" id="tall-1">
                     <label for="tall-1" class="custom-unchecked">Buildings</label>
                 </li>
                 <li>
                     <input type="checkbox" name="tall-2" id="tall-2">
                     <label for="tall-2" class="custom-unchecked">Giants</label>
                     <ul>
                         <li>
                             <input type="checkbox" name="tall-2-1" id="tall-2-1">
                             <label for="tall-2-1" class="custom-unchecked">Andre</label>
                         </li>
                         <li class="last">
                             <input type="checkbox" name="tall-2-2" id="tall-2-2">
                             <label for="tall-2-2" class="custom-unchecked">Paul Bunyan</label>
                         </li>
                     </ul>
                 </li>
                 <li class="last">
                     <input type="checkbox" name="tall-3" id="tall-3">
                     <label for="tall-3" class="custom-unchecked">Two sandwiches</label>
                 </li>
            </ul>
        </li>
        <li class="last">
            <input type="checkbox" name="short" id="short">
            <label for="short" class="custom-unchecked">Short Things</label>
            
            <ul>
                 <li>
                     <input type="checkbox" name="short-1" id="short-1">
                     <label for="short-1" class="custom-unchecked">Smurfs</label>
                 </li>
                 <li>
                     <input type="checkbox" name="short-2" id="short-2">
                     <label for="short-2" class="custom-unchecked">Mushrooms</label>
                 </li>
                 <li class="last">
                     <input type="checkbox" name="short-3" id="short-3">
                     <label for="short-3" class="custom-unchecked">One Sandwich</label>
                 </li>
            </ul>
        </li>
    </ul>
	
	</div>

  <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
  <script src="main.js"></script>
	
</body>

</html>
!

CSS 

              
                
* { margin: 0; padding: 0; }

#page-wrap {
  margin: auto 0;
}

.treeview {
  margin: 10px 0 0 20px;
}

ul { 
  list-style: none;
}

.treeview li {
  background: url(http://jquery.bassistance.de/treeview/images/treeview-default-line.gif) 0 0 no-repeat;
  padding: 2px 0 2px 16px;
}

.treeview > li:first-child > label {
  /* style for the root element - IE8 supports :first-child
  but not :last-child ..... */
  
}

.treeview li.last {
  background-position: 0 -1766px;
}

.treeview li > input {
  height: 16px;
  width: 16px;
  /* hide the inputs but keep them in the layout with events (use opacity) */
  opacity: 0;
  filter: alpha(opacity=0); /* internet explorer */ 
  -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(opacity=0)"; /*IE8*/
}

.treeview li > label {
  background: url(https://www.thecssninja.com/demo/css_custom-forms/gr_custom-inputs.png) 0 -1px no-repeat;
  /* move left to cover the original checkbox area */
  margin-left: -20px;
  /* pad the text to make room for image */
  padding-left: 20px;
}

/* Unchecked styles */

.treeview .custom-unchecked {
  background-position: 0 -1px;
}
.treeview .custom-unchecked:hover {
  background-position: 0 -21px;
}

/* Checked styles */

.treeview .custom-checked { 
  background-position: 0 -81px;
}
.treeview .custom-checked:hover { 
  background-position: 0 -101px; 
}

/* Indeterminate styles */

.treeview .custom-indeterminate { 
  background-position: 0 -141px; 
}
.treeview .custom-indeterminate:hover { 
  background-position: 0 -121px; 
}
!

JS 

              
                $(function() {

  $('input[type="checkbox"]').change(checkboxChanged);

  function checkboxChanged() {
    var $this = $(this),
        checked = $this.prop("checked"),
        container = $this.parent(),
        siblings = container.siblings();

    container.find('input[type="checkbox"]')
    .prop({
        indeterminate: false,
        checked: checked
    })
    .siblings('label')
    .removeClass('custom-checked custom-unchecked custom-indeterminate')
    .addClass(checked ? 'custom-checked' : 'custom-unchecked');

    checkSiblings(container, checked);
  }

  function checkSiblings($el, checked) {
    var parent = $el.parent().parent(),
        all = true,
        indeterminate = false;

    $el.siblings().each(function() {
      return all = ($(this).children('input[type="checkbox"]').prop("checked") === checked);
    });

    if (all && checked) {
      parent.children('input[type="checkbox"]')
      .prop({
          indeterminate: false,
          checked: checked
      })
      .siblings('label')
      .removeClass('custom-checked custom-unchecked custom-indeterminate')
      .addClass(checked ? 'custom-checked' : 'custom-unchecked');

      checkSiblings(parent, checked);
    } 
    else if (all && !checked) {
      indeterminate = parent.find('input[type="checkbox"]:checked').length > 0;

      parent.children('input[type="checkbox"]')
      .prop("checked", checked)
      .prop("indeterminate", indeterminate)
      .siblings('label')
      .removeClass('custom-checked custom-unchecked custom-indeterminate')
      .addClass(indeterminate ? 'custom-indeterminate' : (checked ? 'custom-checked' : 'custom-unchecked'));

      checkSiblings(parent, checked);
    } 
    else {
      $el.parents("li").children('input[type="checkbox"]')
      .prop({
          indeterminate: true,
          checked: false
      })
      .siblings('label')
      .removeClass('custom-checked custom-unchecked custom-indeterminate')
      .addClass('custom-indeterminate');
    }
  }
});
!
999px

Console