<script>
    $(function () {
        $('#<%=pnlDone.ClientID%>').hide();
        $('#<%=pnlOne.ClientID%>').show();

        if (Page_IsValid(""))

            $('#<%=Button1.ClientID%>').click(function () {
                setTimeout(function () {
                    $('#<%=pnlDone.ClientID%>').show();
                    $('#<%=pnlOne.ClientID%>').hide();
                }, 1000);
            });
    });
</script>