I'm dissecting this very beautiful example of how CSS can help you create nice glow effects on images.
http://jsfiddle.net/necolas/KbNq7/
This particular line from the example mentions:
Although this method will only produce the full effect in Firefox 4, other browsers will eventually catch up and apply transitions to pseudo-elements.
What is a pseudo-element?
Pseudo-elements are CSS selectors that manipulate parts of an element in a special way.
They include:
:first-line:before:afterPseudo elements are applied like so
p:first-letter{ color:black; font-style:italic; } Note: the : followed by the selector is how pseudo elements are denoted in CSS1 and CSS2. In CSS3, the double colon is used (::) to distinguish them from pseudo-classes.
More details here: http://reference.sitepoint.com/css/pseudoelements
Support is decent for a number of browsers, with older versions of IE notably poor with support. QuirksMode has a compatibility table (a bit out-of-date but still useful): http://www.quirksmode.org/css/contents.html#t15
Pseudo elements can do some cool things, including
float:center;See more here: http://css-tricks.com/9516-pseudo-element-roundup/
jQuery has a number of unique selectors that enhance and expand on the native CSS group:
http://api.jquery.com/category/selectors/
Note: you can use jQuery to force older browsers to adopt certain rules. For example, IE6 will ignore :last-child. Using jQuery can force IE6 to apply that style.
http://www.w3.org/TR/CSS2/selector.html#pseudo-element-selectors
Its not an element in the dom. Its something you can select with a selector, notably after a :.
