Hi, CSS3 Selectors
An article about CSS3 selectors.
[status: work-in-progress, not-complete]
Resources
Standards Documentation:
http://www.w3.org/TR/2009/PR-css3-selectors-20091215/#selectors
Detailed tables of all the CSS selectors, properties, units implemented by different CSS layout Engines in All the major browsers.
http://en.wikipedia.org/wiki/Comparison_of_layout_engines_(CSS)
A very useful test that checks how much CSS is supported by your Browser.