overlaping menus

I have a problem with overlaping menus. I use the theme "whiteol_v6" field. The test page can be reached at test.feuerwehr-belp.ch . Do you have any idea?

Hi
the best way to start a dicussion is using the word "hello" ...

your template is in cause, line 583 in template.css delete the font-size:0 on
[/code].art-nav
{
background: #FFFFFF;
margin: 0 auto;
position: relative;
z-index: 100;
font-size: 0;
text-align: left;
}[/code]

Thank you very much, that was the solution.