var dom = document.getElementById ? true : false;

 var ie4 = ((document.all) && (!dom)) ? true : false; // IE5 a IE6 znají i zápis s document.all - proto musí být proměnná dom false

 var ns4 = document.layers ? true : false;

 var opera = navigator.userAgent.indexOf('Opera') != -1 ? true : false; // tato proměnná nemá význam pro rozdělení prohlížečů - budete ji potřebovat až při vytváření dynamického menu

 var dhtml = dom ? true : ie4 ? true : ns4 ? true : false;

// zde následuje JavaScriptový kód, který celé dynamické menu vytvoří a rozhýbe
 if (dhtml) document.write
  ('<style type="text/css"> #scriptSupport {display: none;} #menuHolder {position: relative; visibility: hidden; z-index: 1;} #visibleMenu1 {position: absolute; left: -1em; top: 0em;} #visibleMenu2 {position: absolute; left: 2.5em; top: 0em;} #visibleMenu3 {position: absolute; left: 6em; top: 0em;} #visibleMenu4 {position: absolute; left: 15em; top: 0em;} #visibleMenu5 {position: absolute; left: 23em; top: 0em;} #visibleMenu6 {position: absolute; left: 33em; top: 0em;} #visibleMenu7 {position: absolute; left: 41em; top: 0em;} #visibleMenu8 {position: absolute; left: 49em; top: 0em;} #hiddenMenu1 {position: absolute; left: -1em; top: 1.4em; visibility: hidden;} #hiddenMenu2 {position: absolute; left: 2.5em; top: 1.4em; visibility: hidden;} #hiddenMenu3 {position: absolute; left: 6em; top: 1.4em; visibility: hidden;} #hiddenMenu4 {position: absolute; left: 15em; top: 1.4em; visibility: hidden;} #hiddenMenu5 {position: absolute; left: 23em; top: 1.4em; visibility: hidden;} #hiddenMenu6 {position: absolute; left: 33em; top: 1.4em; visibility: hidden;} #hiddenMenu7 {position: absolute; left: 37.5em; top: 1.4em; visibility: hidden;} #hiddenMenu8 {position: absolute; left: 43em; top: 1.4em; visibility: hidden;}</style>');

function setVisibility(element,newVisibility)
{ 
  if (dhtml)
  {
    if (dom) document.getElementById(element).style.visibility = newVisibility;
    else if (ie4) document.all[element].style.visibility = newVisibility;
    else if (ns4) eval('document.' + element + '.visibility = newVisibility');
  }
}

function menu()
{
  if (dhtml)
  {
    if (opera) for (i = 1; i <= 8; i++) document.getElementById('hiddenMenu' + i).style.top = 20;
    if (ie4) for (i = 1; i <= 8; i++) document.all['hiddenMenu' + i].style.top = 18;
    setVisibility('menuHolder','visible');
  }
}

var timer;

function showMenu(id)
{
  if (dhtml)
  {
    clearTimeout(timer);
    for (i = 1; i <= 8; i++) if (i != id) setVisibility((ns4 ? 'menuHolder.document.' : '') + 'hiddenMenu' + i,'hidden');
    setVisibility((ns4 ? 'menuHolder.document.' : '') + 'hiddenMenu' + id,'visible');
  }
}

function hideMenu(id)
{
  if (dhtml)
  {
    menuId = (ns4 ? 'menuHolder.document.' : '') + 'hiddenMenu' + id;
    timer = setTimeout("setVisibility(menuId,'hidden')",50);
  }
}

function dontHideMenu()
{
  if (dhtml) clearTimeout(timer);
}