Thank you very much for you help. This worked and looks good. However, I would like to get a "end-line" at the main menu for the background image ... in the same way that you can specify in the flexible menu.
I got from mike previously a code for the Eventfull tempate this:
#s5_menu_wrap_top {
border-bottom:1px solid #cccccc;}
But it is not working. Any ideas how to solve this?