To add ajax calendar extender with image should pop up below or above the text

I have done like below code, but problem is, it is pop up somewhere in the page., not right below the textbox.(in Google crome only )

So can anyone help me regarding this..

my code is:

<asp:TextBox ID="txt_apptdate" runat="server" CssClass="lefttd" Width="180px" Height="24px"></asp:TextBox>   <cc1:CalendarExtender ID="CalendarExtender3" runat="server" Format="dd/MM/yyyy" TargetControlID="txt_apptdate"                                                     OnClientDateSelectionChanged="checkDate" PopupButtonID="imgCal"/>                                                                                                   &nbsp;&nbsp;<asp:ImageButton ID="imgCal" runat="server" ImageUrl="~/images/calendar.jpg"                                                     CausesValidation="false" />&nbsp;&nbsp;

Pop up is not getting below the textbox in Google crome only

please help me soon