function imgChange(imgID, imgURL)
{
    imgID.src = imgURL;
}

function showPopup(popupName, width) {
    var popup = document.getElementById(popupName);
    if (popup != null)
    {
    var winW = 1024;
    var popup_width = width;

    if (parseInt(navigator.appVersion)>3) {
    if (navigator.appName=="Netscape") {
        winW = window.innerWidth;
    }
    if (navigator.appName.indexOf("Microsoft")!=-1) {
        winW = document.body.offsetWidth;
    }
    }
    popup.style.left = Math.round((winW-popup_width)/2)  + "px";
    popup.style.visibility = "visible";
    }
}
function hidePopup(popupName) {
    var popup = document.getElementById(popupName);
    if (popup != null)
    {
        popup.style.visibility = "hidden";
    }
}