CSS stands for Cascading Style Sheet which is a methodology for seperating the content of the document from the formatting and display properties used to pretty it up for a given media. It is a document format which provides a set of style rules which can then be incorporated into the XHTML document content. Multiple Cascading Style Sheets can be written for the same document as a matter of choice for a visitor, or for different media in which the document will be displayed. A style sheet could be made for a normal webpage displayed in a browser, another for printing, and yet another for display on a mobile phone, to name just a few.
A list of assignments and comments as to completion and scoring as well as links to relevant parts of the homework as requested.
This Winter Wonderland page is an example of a CSS styled XHTML page. I took the Zen template and dumbed it down a lot, then went into Photoshop and created some new graphics of a similar style, mostly to see if I could. The lighthouse in the upper left is a screenshot I took of Activeworlds in the world called Winter. Bach Zhaa was the builder.