var TimeOut = 500;
var cLayer = null;
var cItem = null;
var cLayerNum = 0;
var noClose = 0;
var closeTimer = null;
var sMenuName ="submenu";
var menuName = "menu";

function pulldown(n) {
  var subMenu  = document.getElementById(sMenuName+n);
  var menu = document.getElementById(menuName+n);
	
  if(subMenu) {
    cancelCtime();
    subMenu.style.visibility='visible';
    if(cLayer && (cLayerNum != n))
		cLayer.style.visibility='hidden';
		cLayer = subMenu;
		cItem = menu;
		cLayerNum = n;			
  	} else if(cLayer) {
		cLayer.style.visibility='hidden';
		cLayerNum = 0;
		cItem = null;
		cLayer = null;
 	}
}

function cTimer() {
  closeTimer = window.setTimeout(pdClear, TimeOut);
}

function cancelCtime() {
  if(closeTimer) {
    window.clearTimeout(closeTimer);
    closeTimer = null;
  }
}

function pdClear() {
  if(cLayer && noClose!=1)   {
    cLayer.style.visibility='hidden';
    cLayerNum = 0;
    cLayer = null;
    cItem = null;
  } else {
    noClose = 0;
  }
  cLayer = null;
  cItem = null;
}

document.onclick = pdClear;