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];
}

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

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

        if (isDOM) {
                yMenuFrom   = parseInt (layer_sky.style.top,10);
                yMenuTo     = (isNS ? window.pageYOffset : document.body.scrollTop) +0 ;
        }
        timeoutNextCheck = 500;

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

if (isDOM) {
	var layer_sky = getRef('layer_sky');
	layer_sky.style.top = (isNS ? window.pageYOffset : document.body.scrollTop) + 0;
	layer_sky.style.visibility = "visible";
	moveRightEdge();
}