function opensubmenu(submenu){
  if(submenu=='sub_liefer'){
	document.getElementById('sub_liefer').style.visibility = "visible";
	document.getElementById('sub_leistungen').style.visibility = "hidden";
	document.getElementById('sub_firma').style.visibility = "hidden";
	document.getElementById('sub_kontakt').style.visibility = "hidden";
	document.getElementById('sub_service').style.visibility = "hidden";
  }
  if(submenu=='sub_leistungen'){
	document.getElementById('sub_liefer').style.visibility = "hidden";
	document.getElementById('sub_leistungen').style.visibility = "visible";
	document.getElementById('sub_firma').style.visibility = "hidden";
	document.getElementById('sub_kontakt').style.visibility = "hidden";
	document.getElementById('sub_service').style.visibility = "hidden";
  }
   if(submenu=='sub_firma'){
	document.getElementById('sub_liefer').style.visibility = "hidden";
	document.getElementById('sub_leistungen').style.visibility = "hidden";
	document.getElementById('sub_firma').style.visibility = "visible";
	document.getElementById('sub_kontakt').style.visibility = "hidden";
	document.getElementById('sub_service').style.visibility = "hidden";
  }
   if(submenu=='sub_kontakt'){
	document.getElementById('sub_liefer').style.visibility = "hidden";
	document.getElementById('sub_leistungen').style.visibility = "hidden";
	document.getElementById('sub_firma').style.visibility = "hidden";
	document.getElementById('sub_kontakt').style.visibility = "visible";
	document.getElementById('sub_service').style.visibility = "hidden";
  }
    if(submenu=='sub_service'){
	document.getElementById('sub_liefer').style.visibility = "hidden";
	document.getElementById('sub_leistungen').style.visibility = "hidden";
	document.getElementById('sub_firma').style.visibility = "hidden";
	document.getElementById('sub_kontakt').style.visibility = "hidden";
	document.getElementById('sub_service').style.visibility = "visible";
  }
}
function closesubmenu(){
	document.getElementById('sub_liefer').style.visibility = "hidden";
	document.getElementById('sub_leistungen').style.visibility = "hidden";
    document.getElementById('sub_firma').style.visibility = "hidden";
	document.getElementById('sub_kontakt').style.visibility = "hidden";
	document.getElementById('sub_service').style.visibility = "hidden";
}

function openPopup(meineSeite,meinName,w,h,scroll){
   var LeftPosition = (screen.width) ? (screen.width-w)/2 : 0;
   var TopPosition = (screen.height) ? (screen.height-h)/2 : 0;
   var settings ='height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+',scrollbars='+scroll+',resizable'
   var Fenster = window.open(meineSeite,meinName,settings)
}