var isDOM = (document.getElementById ? true : false);
var isIE4 = ((document.all && !isDOM) ? true : false);
var isNS4 = (document.layers ? true : false);
var isNS = navigator.appName == "Netscape";

function getRef(id) {
if (isDOM) return document.getElementById(id);
if (isIE4) return document.all[id];
if (isNS4) return document.layers[id];
}

function getSty(id) {
x = getRef(id);
return (isNS4 ? getRef(id) : getRef(id).style);
}

var scrollerHeight = 88;
var puaseBetweenImages = 3000;
var imageIdx = 0;

function moveRightEdge() {
var yMenuFrom, yMenuTo, yOffset, timeoutNextCheck;

if (isNS4) {
  yMenuFrom   = divMenu.top;
  yMenuTo     = windows.pageYOffset + 500;   // 图标在页面里的高度
} else if (isDOM) {
  yMenuFrom   = parseInt (divMenu.style.top, 10);
  yMenuTo     = (isNS ? window.pageYOffset : document.body.scrollTop) + 500; // 图标在页面里的高度
}
timeoutNextCheck = 500;

if (yMenuFrom != yMenuTo) {
  yOffset = Math.ceil(Math.abs(yMenuTo - yMenuFrom) / 20);
  if (yMenuTo < yMenuFrom)
   yOffset = -yOffset;
  if (isNS4)
   divMenu.top += yOffset;
  else if (isDOM)
   divMenu.style.top = parseInt (divMenu.style.top, 10) + yOffset;
   timeoutNextCheck = 10;
}
setTimeout ("moveRightEdge()", timeoutNextCheck);
}