I think I am been misunderstood here so I will rephrase my question. THE PROBLEM: when I \"hover\" over the menu the black span with class \"problem\" follows
I'd start by updating the .menu styles thusly:
.menu
float: none; width: 715px; height: 30px; display: block; position: relative; margin: 9px auto;
You'll then need to move the active element behind it, which you can possibly do by applying a negative top-margin
top-margin