The Sakai Style Guide focuses on principles of accessible and usable interface design and the elements designers use to achieve it.
The Guide is primarily for designers but may be of interest to programmers as well. It describes how to design the user interface (UI) of a Sakai application to those developing the JSF and HTML renderings of the application.
See the attached demo files for an overview (demo1) and practical application ([demo2]) of the Style Guide from March 2005.