function backToTop() {
  var x1 = x2 = x3 = 0;
  var y1 = y2 = y3 = 0;
  if (document.documentElement) {
      x1 = document.documentElement.scrollLeft || 0;
      y1 = document.documentElement.scrollTop || 0;
  }
  if (document.body) {
      x2 = document.body.scrollLeft || 0;
      y2 = document.body.scrollTop || 0;
  }
  x3 = window.scrollX || 0;
  y3 = window.scrollY || 0;
  var x = Math.max(x1, Math.max(x2, x3));
  var y = Math.max(y1, Math.max(y2, y3));
  window.scrollTo(Math.floor(x / 2), Math.floor(y / 2));
  if (x > 0 || y > 0) {
      window.setTimeout("backToTop()", 25);
  }
}



var TimeOut         = 300;
var currentLayer    = null;
var currentitem     = null;
var currentLayerNum = 0;
var noClose         = 0;
var closeTimer      = null;

function mopen(n) {
  var l  = document.getElementById("menu" + n);
  var mm = document.getElementById("mmenu" + n);
	
  if(l) {
    mcancelclosetime();
    l.style.visibility='visible';
    if(currentLayer && (currentLayerNum != n))
      currentLayer.style.visibility='hidden';
    currentLayer = l;
    currentitem = mm;
    currentLayerNum = n;			
  } else if(currentLayer) {
    currentLayer.style.visibility='hidden';
    currentLayerNum = 0;
    currentitem = null;
    currentLayer = null;
 	}
}

function mclosetime() {
  closeTimer = window.setTimeout(mclose, TimeOut);
}

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

function mclose() {
  if(currentLayer && noClose!=1)   {
    currentLayer.style.visibility='hidden';
    currentLayerNum = 0;
    currentLayer = null;
    currentitem = null;
  } else {
    noClose = 0;
  }
  currentLayer = null;
  currentitem = null;
}

document.onclick = mclose; 
