CSS References

Cascading Style Sheets, Level 1: The W3C's Recommendation gives the complete specification for CSS1.
Cascading Style Sheets, Level 2: CSS2 provides numerous additions to CSS1, few of which are supported by browsers.
Cascading Style Sheets: The W3C's CSS home with links to CSS news, tutorials, browsers, and authoring tools.
CSS Frequently Asked Questions: A thorough list of frequently asked questions concerning CSS.
CSS Pointers: A comprehensive list of well-selected CSS links.
CSS Bugs/Workarounds: A listing of bugs and workarounds for widely used CSS browsers.
The House of Style: Includes a CSS handbook and tutorial, and a detailed look at browser support.
CSS1 support in Microsoft Internet Explorer 3.0: A look at CSS1 bugs and missing support in Microsoft Internet Explorer 3.0 for Windows 95 & NT 4.0.
Web Review Style Sheets Reference Guide: Helpful articles and the always-popular Browser Compatibility Charts.
Style Sheets Known Issues: Bugs and unsupported features in Netscape Navigator 4.0's CSS implementation.
CSS support in Amaya: Documentation of the CSS support in Amaya, the W3C's test-bed browser.