window.setInterval("MoveDoc()", 10);

function ShowCertificate()
{
    document.getElementById("container_preview_cert").style.display = "block";
    document.getElementById("container_preview_cert").style.width = "0px";
    document.getElementById("container_preview_cert").style.height = "0px";
    
    document.getElementById("back_preview_cert").style.position = "absolute";
    document.getElementById("back_preview_cert").style.left = 0;
    document.getElementById("back_preview_cert").style.top = 0;
    
    document.getElementById("back_preview_cert").style.width = document.body.offsetWidth + "px";
    document.getElementById("back_preview_cert").style.height = document.body.offsetHeight + "px";
    
    document.getElementById("preview_cert").style.position = "absolute";
    document.getElementById("preview_cert").style.left = ((document.body.offsetWidth / 2) - 420) + "px";
    document.getElementById("preview_cert").style.top = (document.documentElement.scrollTop + 150) + "px";
}

function MoveDoc(e)
{
    document.getElementById("preview_cert").style.top = (document.documentElement.scrollTop + 150) + "px";
}