I have a repeater control which on clicking opens a web data menu which opens items as primary menu. The menu opened in a div with CSS set to "overflow:hidden", which opens the primary menu in the panel. When CSS (overflow:hidden) is removed, the primary menu creates an extra space below the page footer.

The code snippet is given below. The screenshots are also attached for further clarification.

<div id="leftpanel_bg" class="leftpanel_bg" style="display:none;"></div>
<div id="leftPanel" class="leftPanel">
<div id="navigation" class="leftPanelContent nodisplay">
<asp:Repeater ID="rptParent" runat="server" OnItemDataBound="rptParent_ItemDataBound">
<HeaderTemplate>
<table width="100%" border="0" cellpadding="0" cellspacing="0" >
</HeaderTemplate>
<ItemTemplate>
<tr>
<td>
<div class="left-menuspacer">
</div>
</td>
</tr>
<tr>
<td class="left-menurow">
<div class="left-menuplus">
<asp:HiddenField ID="hdnFldToggleState" runat="server" Value="1" />
<asp:HiddenField ID="hdnEmployeeParentId" runat="server" Value='<%#Eval("EmpID") %>' />
<asp:HiddenField ID="hdnEmployeeParentName" runat="server" Value='<%#Eval("Name") %>' />
<asp:HiddenField ID="hdnLastFeedbackDate" runat="server" Value='<%#Eval("LastFeedbackDate")%>' />
<asp:ImageButton ID="imgBtnNode" runat="server" ImageUrl="~/TalentfirstV3/Images/icon_plus.png"
OnClientClick="ToggleChildItem()" />
</div>
<div style="float: left;">
<ig:WebDataMenu runat="server" ID="ContextMenuParent" IsContextMenu="false" EnableScrolling="false"
ActivateOnHover="false" CloseMenuOnClick="false" EnableExpandOnClick="false">
<ClientEvents ItemSelecting="WebDataMenu1Client_ItemSelecting" />
<%--<ClientEvents ItemClick="ContextMenu_ItemClick" />--%>
<Items>
<ig:DataMenuItem Key="TopItem" TemplateId="ParentMenu">
<Items>
<ig:DataMenuItem Text="Provide Feedback" Key="ProvideFeedBack" CssClass="dtMenuParentitem">
<Items>
<ig:DataMenuItem Key="Reports" />
<ig:DataMenuItem Key="ActionRequired" />
<ig:DataMenuItem Key="QuickFeedback" />
<ig:DataMenuItem Key="DistanceCoaching" />
</Items>
</ig:DataMenuItem>
<ig:DataMenuItem Text="Assign Training" Key="AssignTraining" CssClass="dtMenuParentitem" />
<ig:DataMenuItem Text="Assess Proficiency" Key="AssessProficiency" CssClass="dtMenuParentitem" />
<ig:DataMenuItem Text="Request Self-Assessment" Key="RequestAssessment" CssClass="dtMenuParentitem" />
<ig:DataMenuItem Text="Request Multi-rater Feedback" Key="RequestMultiFeedback" CssClass="dtMenuParentitem" />
<ig:DataMenuItem Text="Review Goals" Key="ReviewGoals" CssClass="dtMenuParentitem" />
</Items>
</ig:DataMenuItem>
</Items>
<Templates>
<ig:ItemTemplate TemplateID="ParentMenu">
<Template>
<div class="left-menuimage">
<asp:Image ID="imgEmployee" runat="server" />
</div>
<div class="left-menutext" style="width: 250px; word-wrap: break-word;">
<span class="LftPnlName">
<asp:Label ID="lblName" runat="server"></asp:Label>
</span><span class="LftPnlfeedback">Last Feedback:
<asp:Label ID="lblfeedbackDate" runat="server"></asp:Label>
</span>
</div>
</Template>
</ig:ItemTemplate>
</Templates>
</ig:WebDataMenu>
</div>
</td>
</tr>

</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
</div>
<div class="HNewsBtn">
<img runat="server" id="newsPlusClick" src="~/TalentFirstv3/images/my_team_col.png"
title="My Team" alt="My Team" />
</div>
</div>

The zip file containing the screenshots of my probelm.

Thanks.