C# – Keep page position on postback

I have a problem:

<asp:Label ID="Label1" runat="server" Text="Name" CssClass="left"></asp:Label>

    <asp:LinkButton ID="LinkEdit" runat="server" CssClass="right_bottom" 
        onclick="LinkEdit_Click" Height="16px">edit</asp:LinkButton>
    <asp:LinkButton ID="Linkhide" runat="server" CssClass="right_bottom" 
        onclick="Linkhide_Click" Visible="False" hide</asp:LinkButton>
    <br />
    <hr style="width: 740px; height: -6px; margin-left: 0px; " />
    <asp:Label ID="labelFullname" runat="server" Text="Full Name" CssClass="left_top"></asp:Label>
    <asp:Label ID="labelNameDisplay" runat="server" Text="Put name here" CssClass="right_top"></asp:Label>

    <br />
    <asp:Panel ID="panelName" runat="server" Height="240px" Visible="False" CssClass="panel_top"
        style="text-align: left;">
        
        <asp:Label ID="Label8" runat="server" CssClass="left" Text="Please allow 24 hours for name changes to take effect."></asp:Label>
    <div align="center"><br />
    <br />
    <table>
       <tr>
       <td class="label_new">
         <asp:Label ID="Label4" runat="server" Text="Full Name:" ToolTip="Name Displayed"></asp:Label>
         </td>
         <td align="left">
          
          <asp:DropDownList ID="DropDownList1"  runat="server" BorderStyle="Groove" 
                 Font-Names="Segoe UI,Tahoma,Verdana,Arial,Times" Font-Size="100%" Height="25px" 
          valign="middle" Width="250px">
              <asp:ListItem></asp:ListItem>
              <asp:ListItem></asp:ListItem>
              <asp:ListItem></asp:ListItem>
          </asp:DropDownList>
       </td>
  </tr>
  

   <tr>
       <td class="label_new">
         <asp:Label ID="Label2" runat="server" Text="First Name:"></asp:Label>
         </td>
         <td align="left">
         <asp:TextBox ID="txtFirstName" runat="server" BorderStyle="Groove" Font-Names="Segoe UI,Tahoma,Verdana,Arial,Times" Font-Size="100%" Height="20px" 
          valign="middle" Width="242px"></asp:TextBox>
       </td>
  </tr>

     <tr>
       <td class="label_new">
         <asp:Label ID="Label9" runat="server" Text="Middle Name:"></asp:Label>
         </td>
         <td align="left">
         <asp:TextBox ID="txtMiddleName" runat="server" BorderStyle="Groove" Font-Names="Segoe UI,Tahoma,Verdana,Arial,Times" Font-Size="100%" Height="20px" 
          valign="middle" Width="242px" onfocus="if (this.value == 'optional') {   this.value='';  this.style.color='black';}" />
       </td>
  </tr>

     <tr>
       <td class="label_new">
         <asp:Label ID="Label10" runat="server" Text="Last Name:"></asp:Label>
         </td>
         <td align="left">
         <asp:TextBox ID="txtLastName" runat="server" BorderStyle="Groove" Font-Names="Segoe UI,Tahoma,Verdana,Arial,Times" Font-Size="100%" Height="20px" 
          valign="middle" Width="242px"></asp:TextBox>
       </td>
  </tr>
  <tr>
  <td colspan="2">
      <asp:Button ID="btnSaveChanges" runat="server" Text="Save Changes" 
          onclick="btnSaveChanges_Click" />
  </td>
  </tr>
    </table>
    </div>
   
    </asp:Panel>

I have 4 panels in this format just like ACCOUNT SETTINGS on facebook.
My problem here is when I show the panel it just jump to the top of the page.

I would like to do it just as the way facebook is doing. Click and be on at the same position of where you clicked.