Using Empty Span Tags with H2 Headers for Image Replacement
In this eighth installment of a series on image replacement techniques, you'll learn how to use Fahrner’s enhanced image replacement method for styling all of the H2 elements included in a sample web document. This method uses two empty <span> tags in a clever way which permits you to efficiently solve the problem caused by broken background images.
Using Empty Span Tags with H2 Headers for Image Replacement - Review: the enhanced Fahrner's IR technique (Page 2 of 4 )
First I'd like to review the use of the improved version of Fahrner’s image replacement technique with a single H1 element of a web document. Below I relisted the source code corresponding to this specific example, so you can recall (or learn) its driving logic.
With that being said, first here’s the background image that was used to decorate the H1 header:
And here’s the XHTML document that puts the Fahrner’s enhanced technique in action:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<title>Variation of Fahrner Image Replacement (FIR) on H1 elements</title>
<style type="text/css">
body {
padding: 0;
margin: 0;
background: #fff;
font: 1em Arial, Helvetica, sans-serif;
color: #000;
}
#wrapper {
width: 960px;
margin: 0 auto;
background: #ffc;
}
#header, #content, #footer {
padding: 20px;
}
/* apply image replacement on H1 element */
#header h1 {
position: relative;
width: 400px;
height: 200px;
margin: 0;
padding: 0;
overflow: hidden;
}
#header h1 span {
display: block;
position: absolute;
left: 0;
top: 0;
z-index: 1;
width: 400px;
height: 200px;
margin: 0;
padding:0;
background: url(h1.gif) top left no-repeat;
}
</style>
</head>
<body>
<div id="wrapper">
<div id="header">
<h1>Welcome to our website<span></span></h1>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse auctor commodo risus, et ultrices sapien vestibulum non. Maecenas scelerisque quam a nulla mattis tincidunt. Etiam massa libero, pharetra vel laoreet et, ultrices non leo. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed posuere ullamcorper lacus et sollicitudin. Morbi ultrices condimentum lacus, sit amet venenatis purus bibendum sit amet. Quisque rhoncus sodales sapien ac blandit. Nam lacus urna, commodo eget tincidunt vitae, ullamcorper at nulla. Vivamus ac iaculis justo. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Aliquam erat volutpat. Sed quis elit erat, et ultricies diam. Phasellus non turpis malesuada erat ultrices tincidunt sed vitae magna. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Duis purus risus, lacinia at faucibus id, luctus nec diam. In nulla neque, consequat ac hendrerit ac, pulvinar eu dui. Aenean in arcu felis, non hendrerit est.</p>
</div>
<div id="content">
<h2>Main content section</h2>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse auctor commodo risus, et ultrices sapien vestibulum non. Maecenas scelerisque quam a nulla mattis tincidunt. Etiam massa libero, pharetra vel laoreet et, ultrices non leo. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed posuere ullamcorper lacus et sollicitudin. Morbi ultrices condimentum lacus, sit amet venenatis purus bibendum sit amet. Quisque rhoncus sodales sapien ac blandit. Nam lacus urna, commodo eget tincidunt vitae, ullamcorper at nulla. Vivamus ac iaculis justo. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Aliquam erat volutpat. Sed quis elit erat, et ultricies diam. Phasellus non turpis malesuada erat ultrices tincidunt sed vitae magna. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Duis purus risus, lacinia at faucibus id, luctus nec diam. In nulla neque, consequat ac hendrerit ac, pulvinar eu dui. Aenean in arcu felis, non hendrerit est.</p>
</div>
<div id="footer">
<h2>Footer section</h2>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse auctor commodo risus, et ultrices sapien vestibulum non. Maecenas scelerisque quam a nulla mattis tincidunt. Etiam massa libero, pharetra vel laoreet et, ultrices non leo. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed posuere ullamcorper lacus et sollicitudin. Morbi ultrices condimentum lacus, sit amet venenatis purus bibendum sit amet. Quisque rhoncus sodales sapien ac blandit. Nam lacus urna, commodo eget tincidunt vitae, ullamcorper at nulla. Vivamus ac iaculis justo. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Aliquam erat volutpat. Sed quis elit erat, et ultricies diam. Phasellus non turpis malesuada erat ultrices tincidunt sed vitae magna. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Duis purus risus, lacinia at faucibus id, luctus nec diam. In nulla neque, consequat ac hendrerit ac, pulvinar eu dui. Aenean in arcu felis, non hendrerit est.</p>
</div>
</div>
</body>
</html>
As the previous example shows, the correct implementation of Fahrner’s improved method requires coding two <span> tags that are positioned absolutely with reference to their relatively-placed parent, which in this case is the targeted H1 element itself. This combination permits you to easily overlap the assigned background image with the element’s inner text, thus achieving the desired image replacement.
And finally, if you run the above example on your browser, you should get a rendered XHTML page similar to the one depicted below:
As I stated in the introduction, even when this IR method does use additional empty markup to do its thing, it effectively solves the problem that arises when the background image assigned to the selected web page element isn’t downloaded properly by the browser. After all, coding two extra <span> tags isn’t that bad, right?
Now that you've grasped the underlying logic of Fahrner’s improved technique, it’s time to see how this method can be used for decorating all of the H2 elements of the web page that you saw before.
To learn the full details of this process, please click on the link below and read the section to come.
Style Sheets 
HTML5 Boilerplate Introduction
