var divLightBox;
function InitPage() {
    divLightBox = new YAHOO.widget.Overlay(LightBoxId, { visible: false, width: "920px", height: "630px" });
    divLightBox.render();
}
//overlay helper functions
function OpenOverlay() {
    Reposition_Curtain();

    var divCurtain = YAHOO.util.Dom.get(CurtainId);
    YAHOO.util.Dom.setStyle(divCurtain, "display", "block");

    divLightBox.cfg.setProperty("height", "630px");
    divLightBox.cfg.setProperty("width", "920px");
    //$(divLightBox).css("height", "470");

    divLightBox.show();

    Reposition_Overlay();
}

var Reposition_Overlay = function() {
    divLightBox.center();
}

function CloseOverlay() {
    var divCurtain = YAHOO.util.Dom.get(CurtainId);
    YAHOO.util.Dom.setStyle(divCurtain, "display", "none");

    divLightBox.cfg.setProperty("height", "0px");
    //$(divLightBox).css("height", "0");
    divLightBox.hide();
}
var Reposition_Curtain = function() {
    var divCurtain = YAHOO.util.Dom.get(CurtainId);

    var docHeight = YAHOO.util.Dom.getDocumentHeight();
    var docWidth = YAHOO.util.Dom.getDocumentWidth();

    divCurtain.style.width = docWidth + "px";
    divCurtain.style.height = docHeight + "px";
}