function showhide(item) {
	obj=document.getElementById(item);
   	visible=(obj.style.display!="none")
   	key=document.getElementById("x" + item);
   		
   	if (visible) {
    	obj.style.display="none";
    	key.innerHTML="colofon";
   	} else {
     	
    	obj.style.display="block";
    	key.innerHTML="verberg";
   	}
}