How can I make my Modal Popup Extender Modal? (Disable background)

Question

I added a simple ajax modal popup extender to my asp.net application.

It appears and functions correctly, however unlike the sample on the ajax toolkit website, it does not disable/dim the rest of the page. What do I have to do to achieve this effect?

 <asp:Button ID="btnSaveAndClose" runat="server" Text="Save" 
                onclick="btnSaveAndClose_Click"/>

                <cc1:ModalPopupExtender 
                BackgroundCssClass="modalBackground" 
                DropShadow="true" 
                OkControlID="btnOk" 
                CancelControlID="btnOk" 
                runat="server" 
                PopupControlID="pnlClientSaved" 
                id="ModalPopupExtender1" 
                TargetControlID="btnSaveAndClose"
                 /> 

<asp:Panel ID="pnlClientSaved" runat="server" CssClass="modalPopup" style="display:none;" Width="300px" Height="200px"> 
Client Saved!
<br /><br /> 
<asp:Button ID="btnOk" runat="server" Text="Ok" /> 
</asp:Panel>

Answer 1

You should write an appropriate style in "modalBackground" css class. Appropriate property was already set in you code:

BackgroundCssClass="modalBackground"

Here is listing of this class from example page:

.modalBackground 
{
    background-color:Gray;
    opacity:0.7;
}