I am a server-side programmer that is proficient in Java. I have fairly good knowledge of client-side scripting - primarily Javascript - but my ability in CSS is lacking. While I have the know-how to modify basic styles, I'd like to understand a bit more about CSS layouts and styling. Can anyone with expert knowledge of CSS provide a good source for diving into the topic? Also, are there any short, online courses that might help in gaining the information I seek?