if (document.all) document.getElementById = document.all;
var dhtml = (document.getElementById || document.all) && navigator.userAgent.indexOf('Opera') == -1 ? true : false;

if (dhtml)
{
  var folder_closed = document.createElement('img');
  folder_closed.setAttribute('src','img_menu/folder-closed.gif');
  
  var plus_cross = document.createElement('img');
  plus_cross.setAttribute('src','img_menu/plus-cross.gif');
  
  var plus_corner = document.createElement('img');
  plus_corner.setAttribute('src','img_menu/plus-corner.gif');
  
  var folder_open = document.createElement('img');
  folder_open.setAttribute('src','img_menu/folder-open.gif');
  
  var minus_cross = document.createElement('img');
  minus_cross.setAttribute('src','img_menu/minus-cross.gif');
  
  var minus_corner = document.createElement('img');
  minus_corner.setAttribute('src','img_menu/minus-corner.gif');
  
  document.write('<style type="text/css">#menuHolder{visibility: hidden;}' + (document.all && (!document.getElementById || !document.getElementsByTagName) ? '#menuHolder img {vertical-align: text-top;}' : '') + '</style>');
}

function loadMenu()
{
  // i = 1 - pro cele menu
  for (i = 4; i <= 7; i++) 
  menuClick(i, i == 3 || i == 7 ? true : false); // koncove menu - ano/ne
  document.getElementById('menuHolder').style.visibility = 'visible';
}

function menuClick(id,last)
{
  if (dhtml)
  {
    document.getElementById('menu' + id).style.display = (displayed[id] ? 'none' : 'block');
    if (!last) document.getElementById('marker' + id).setAttribute('src',displayed[id] ? plus_cross.getAttribute('src') : minus_cross.getAttribute('src'));
    else document.getElementById('marker' + id).setAttribute('src',displayed[id] ? plus_corner.getAttribute('src') : minus_corner.getAttribute('src'));
    document.getElementById('folder' + id).setAttribute('src',displayed[id] ? folder_closed.getAttribute('src') : folder_open.getAttribute('src'));
    displayed[id] = (displayed[id] == true ? false : true);
  }
}