function res() {
vis=document.getElementById('mmenu').offsetHeight;
if(vis>34){document.getElementById('mmenu').style.background="url('pic/mmgradbig.png') repeat-x #f2f2f2";}
if(vis<34){document.getElementById('mmenu').style.background="url('pic/mmgrad.png') repeat-x #f2f2f2";}
}