How to Use the CSS Z-index Property

See CSS: Tips and Tricks for similar articles.

The z-index property specifies the stack level of an element on the page compared to other elements in its same flow. Learn how to use the z-index property in the following steps.

  1. Set the z-index property for a selector.

    The z-index property takes a number as a value. The higher an element's z-index value, the closer to the user it appears.

  2. 
    .logo {
    	position:absolute;
    	top: 70px;
    	left: 50px;
    	z-index: 20;
    }
    	
  3. To see how the z-index property works, position another element so that it overlaps the first element and give it a different z-index value.
  4. 
    .logo {
    	position:absolute;
    	top: 70px;
    	left: 50px;
    	z-index: 20;
    }
    .logo2 {
    	position:absolute;
    	top: 75px;
    	left: 55px;
    	z-index: 10;
    }
    	
  5. The following example demonstrates the z-index property:
    <!DOCTYPE HTML>
    <html>
    <head>
    <meta charset="UTF-8">
    <style type="text/css">
    .logo {
    	position:absolute;
    	font-family:Century;
    	font-size:2em;
    	font-weight:bold;
    	z-index:20;
    }
    #logo1 {
    	left:50px;
    	top:50px;
    	color:#00f;
    }
    #logo2 {
    	left:52px;
    	top:52px;
    	color:#f00;
    	z-index:10;
    }
    .box {
    	position:absolute;
    	height:100px;
    	width:100px;
    	border:15px solid #000;
    }
    #box1 {
    	left:150px;
    	top:150px;
    	border-color:#f00;
    	z-index:40;
    }
    #box2 {
    	left:185px;
    	top:185px;
    	border-color:#00f;
    	z-index:30;
    }
    #box3 {
    	left:185px;
    	top:150px;
    	border-color:#060;
    	z-index:20;
    }
    #box4 {
    	left:150px;
    	top:185px;
    	border-color:#f60;
    	z-index:10;
    }
    </style>
    <title>CSS Z-Index</title>
    </head>
    <body>
    	<h1>CSS Z-Index</h1>
    	<div id="logo1" class="logo">Webucator</div>
    	<div id="logo2" class="logo">Webucator</div>
    	<div id="box1" class="box"></div>
    	<div id="box2" class="box"></div>
    	<div id="box3" class="box"></div>
    	<div id="box4" class="box"></div>
    </body>
    </html>
    This code renders the following: z-index demo