CSS: fit background image to table width onmouseove efect

I would like to create menu with following on mouse over effect: When you went with mouse over a link in menu, there should appear background image which will fit to text size. Example like it is on [login to view URL] (top menu). The main problem is that I cannot integrate this digg's CSS in my code. Attached is picture ([login to view URL]) which shows what I would like to have. Attached is also [login to view URL] file where is both – working CSS form Digg’s web site and my menu. On my account I have 28$ left so the project price is 28$.