function zobraz(menu) {
    disp = menu.style.display;
    if (disp!="none") { //skryj menu
        menu.style.display = "none";
    } else { //zobraz menu
        menu.style.display = "block";
    }
}

//------------------------ submenu
var zobrazeno;
function ukazSub(id, zobraz) {
    if (id != "") {
        if (zobraz)    {
            if (zobrazeno) { document.all[zobrazeno].style.visibility = "hidden"; window.clearTimeout(timeout);}
            document.all[id].style.visibility = "visible";
            zobrazeno = id;
        } else {        
            timeout = window.setTimeout("document.all['"+id+"'].style.visibility = 'hidden'",500);
        };
    }
}