Css3 selectors - sinsunsan/archiref_wiki GitHub Wiki

http://net.tutsplus.com/tutorials/html-css-techniques/the-30-css-selectors-you-must-memorize
Excellent post on all selectors includes some less known css 3 selector

a:active
When the url of the page is the same that the url in the href attribute of the a tag

a:after

p + p All p that are precedated by a p p
p
p
Only the last 2 p will be selected