Well, it's sort of rubbish and half-finished, but it's available here:
Home - Xav's Net Site
I don't have the CSS to hand, but I can tell you what it is:
@ The external CSS file contains the class "sidebar_heading", which contains the "width: 50px;" line (the other properties in the class work fine).
@ The CSS file is linked via a <link> tag. All the other styles work, including the background-color / text colour in the sidebar_heading class.
@ The cell links the CSS file, as in <td class="sidebar_heading">.
Is this enough info?