function initBackground() {
    aSizes = getSizes();
    document.getElementById("container").style.height = aSizes[1]+"px";
}

function getScroll(){
    if (self.pageYOffset) {
        yScroll = self.pageYOffset;
    } else if (document.documentElement && document.documentElement.scrollTop) { // Explorer 6 Strict
        yScroll = document.documentElement.scrollTop;
    } else if (document.body) { // all other Explorers
        yScroll = document.body.scrollTop;
    }

    aScroll = new Array("",yScroll)
    return aScroll;
}

function getSizes() {
    if (window.innerHeight && window.scrollMaxY) {
        xScroll = document.body.scrollWidth;
        yScroll = window.innerHeight + window.scrollMaxY;
    } else if (document.body.scrollHeight > document.body.offsetHeight) { // all but Explorer Mac
        xScroll = document.body.scrollWidth;
        yScroll = document.body.scrollHeight;
    } else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
        xScroll = document.body.offsetWidth;
        yScroll = document.body.offsetHeight;
    }

    var windowWidth, windowHeight;
    if (self.innerHeight) { // all except Explorer
        windowWidth = self.innerWidth;
        windowHeight = self.innerHeight;
    } else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
        windowWidth = document.documentElement.clientWidth;
        windowHeight = document.documentElement.clientHeight;
    } else if (document.body) { // other Explorers
        windowWidth = document.body.clientWidth;
        windowHeight = document.body.clientHeight;
    }

    // for small pages with total height less then height of the viewport
    if (yScroll < windowHeight){
        pageHeight = windowHeight;
    } else {
        pageHeight = yScroll;
    }

    // for small pages with total width less then width of the viewport
    if (xScroll < windowWidth){
        pageWidth = windowWidth;
    } else {
        pageWidth = xScroll;
    }

    aSizes = new Array(pageWidth,pageHeight,windowWidth,windowHeight);
    return aSizes;
}

function showVideo() {
    aSizes  = getSizes();
    aScroll = getScroll();

    iWidth = 560;
    iHeight = 339;

    document.getElementById("overlayVideo").style.height = aSizes[1]+"px";
    document.getElementById("overlay-bg").style.height = aSizes[1]+"px";

    iContentTop = aScroll[1] + ((aSizes[3] - (iHeight+10)) / 2);
    iContentLeft = (aSizes[0] - (iWidth+10)) / 2;

    document.getElementById("overlay-content").style.top = iContentTop+"px";
    document.getElementById("overlay-content").style.left = iContentLeft+"px";

    document.getElementById("overlay-close").style.top  = (iContentTop-17)+"px";
    document.getElementById("overlay-close").style.left = (iContentLeft+iWidth-90+10)+"px";

    so.write("overlay-content");

    document.getElementById("overlayVideo").style.visibility = "visible";
}

function hideVideo() {
    document.getElementById("overlay-content").innerHTML = "";
    document.getElementById("overlayVideo").style.visibility = "hidden";
}