function close_vid() {
    var oVidPlayer = document.getElementById("video_player");
    oVidPlayer.style.visibility = "hidden";
}

function Show_Video() {
    var oVidPlayer = document.getElementById("video_player");
    var iTop;
    var iWidth = document.documentElement.offsetWidth / 2 - 175;
    if (navigator.appName == "Microsoft Internet Explorer") {
        iTop = document.documentElement.scrollTop + 100;
    } else {
        //iTop = document.body.scrollTop + 100;
        iTop = window.pageYOffset + 100;
    }

    oVidPlayer.style.top = iTop + "px";
    oVidPlayer.style.left = iWidth + "px";
    oVidPlayer.style.visibility = "visible";

}