//==================================================================================================
// For popup menu
//==================================================================================================
 var curr_menu = null;
 var curr_menu_owner = null;
 var curr_left;
 var curr_right;
 var curr_top;
 var curr_bottom;

 // Simple Javascript Browser/OS detection (based on "Harald Hope, Tapio Markula, http://techpatterns.com ver 2.0.1")
 var ua = navigator.userAgent;

 var is_opera = ( ua.indexOf( 'Opera' ) != -1 );
 var is_ie    = ( document.all && !is_opera );
 var is_firefox = ( ua.indexOf( 'fox' ) != -1 );

 function hide_all_menus(x,y) {

//  var yy = event.y + document.body.scrollTop; // так FireFox не понимает

  var yy = y + document.body.scrollTop;
  if (curr_menu!=null)
      if (x>curr_right) {
          curr_menu.style.visibility = "hidden";
          curr_menu = null;
         }
         else if (x<curr_left) {
                  if (yy>curr_top+curr_menu_owner.height || yy<=curr_top) {
                          curr_menu.style.visibility = "hidden";
                          curr_menu = null;
                         }
                 }
                 else if (yy>curr_bottom || yy<=curr_top) {
                          curr_menu.style.visibility = "hidden";
                          curr_menu = null;
                         }
 }

 function show_menu (who,owner) {

  if (who==null) return;
  var element = document.getElementById(owner);
  var left = element.offsetLeft;
  var top = element.offsetTop;
  for (var parent = element.offsetParent; parent; parent = parent.offsetParent) {
       left += parent.offsetLeft;
       top += parent.offsetTop;
      }
  // Прежде, чем показать другое меню, прячем предыдущее видимое выпадающее меню
  if (curr_menu!=null) {
      curr_menu.style.visibility = "hidden";
      curr_menu = null;
     }
  left = left + element.width;
  var awidth = 150;
  who.style.left = left;
  who.style.top = top;
  who.style.width = awidth;
  who.style.visibility = "visible";

  curr_menu = who;
  curr_menu_owner = element;
  curr_left = left;
  curr_right = left + awidth;
  curr_top = top;
  curr_bottom = top + 25 * who.acount;
 }

 function button_on(aid) {
  var d = document.getElementById(aid);
//  d.style.background.url="imagesa/button_on.jpg"; // так нельзя
  // так правильнее
  d.style.background="url('imagesa/button_on.jpg') repeat-x";//"imagesa/button_off.jpg";
 }

 function button_off(aid) {
  var d = document.getElementById(aid);
  // так правильнее
  d.style.background="url('imagesa/button_off.jpg') repeat-x";//"imagesa/button_off.jpg";
 }