CSS Library: Other: Here
CSS Generated Content
Author: Dynamic Drive
CSS2 supports the insertion of generated content, which is content that's specified using your style sheet and applied dynamically to the page according to your CSS definition. This is very useful for further decorating an element with rich content that should not be part of the page's actual markup. CSS Generated Content is accomplished using the ":before" and ":after" pseudo-classes, which denotes whether the content should be added before or after the element in question. You can insert regular "string" content or an embedded object (ie: an image). CSS2's Generated Content is supported in Mozilla/Firefox and Opera 7+, and IE7+
In our first example, we'll automatically add the decorative text ":: " in front of all H3 headers using CSS generated content, and make it red as well:
Dynamic Drive CSS Library
If you're using a capable browser, you should see the effect.
In the next example, you'll see how to include an image as part of the generated content: