Foi desenvolvida uma nova técnica que permite dar um efeito de borda interna, em imagens, ao passar o mouse por cima da mesma.

Gerador de esquema de cores.

Como fazer efeito de transparencia utilizando CSS. Irado.

Como fazer um menu em forma de abas. The Ultimate Tabbed Menu goes through the steps of making a tabbed menu, and provides a variety of styles and colors in the included download pack.

This document is meant for people who know the basics of CSSi, but may not be as familiar as they could be with positioning and the idea of specificity. We're not trying to cover everything there is to know about CSS, because it's one page on one Web site

At W3Schools you will find all the Web-building tutorials you need, from basic HTML and XHTML to advanced XML, SQL, Database, Multimedia and WAP.

This is the W3C Markup Validation Service, a free service that checks Web documents in formats like HTML and XHTML for conformance to W3C Recommendations and other standards.