function toggle(item, img) {
   it = document.getElementById(item);
   im = document.getElementById(img);
   
   if ( it.style.display == "none" ) { 
     it.style.display = "";
     im.src = "minus.gif";
     im.alt = "-";
   } else {
     it.style.display = "none";
     im.src = "plus.gif";
     im.alt = "+";
   }
 }
 
 function toggleClass(name, check) {
   ch = document.getElementById(check);
   state = ch.checked;
   
   _toggleClass(document.body, name, state);    
 }
 
 function _toggleClass(item, name, check) {
   if ( item.className == name ) {
     if ( check )
       item.style.display = "";
     else
       item.style.display = "none";
   }
   
   var i;
   
   for ( i = 0; i < item.childNodes.length; i++ ) {
     // if ( item.childNodes.item(i) instanceof HTMLElement )
       _toggleClass(item.childNodes.item(i), name, check);
   }
 }
 
 function toggleArray(item, check) {
   for ( i = 0; i < item.length; i++)
     if ( item[i].style.display == "none" ) {
       item[i].style.display = "";
       check.checked = true;
     } else {
       item[i].style.display = "none";
       check.checked = false;
     }
 }