Arrow mouse over code completed.  Next on deck, changing headline text.
Rewrote the logic code using a case statement. Added the changing H1 and H2 text. For version three, I will adjust the CSS to make the hover text look more like the 37Sginals website.
Added the CSS.
Adjusted the CSS table of contents. Finito.
Spelling correction and comments adjustments.
Removed trakcing from typeface files that were moved into a folder.