>>http://www.w3.org/TR/2001/CR-css3-selectors-20011113/
http://kimblim.dk/csstest/
>>===CSS===
Cascading Style Sheets can be applied to all views, or specific views such as display or printer.

==debug==
My favorite CSS debug tip just use the EditCSS BurningDog or Firefox or IceWeasel addon to insert the following CSS snippet
%%
* { border : 1px dotted salmon }
%%
and you'l get dotted pink lines around every element on your page

==:after==
Here's an example of using the ::after pseudo-element to display the URL of every href on your page - very useful for printer CSS. 
But best used with an "external" class so you don't print EVERY link !

%%(css)
a::after
{
	content: " (" attr(href) ") ";	
}
%%