Display panel below the Visible Panel

I am having 4 panels in a div my aspx page. If I make panel2 visible first and want to make panel1 visible from panel2, Panel1 is displaying on top of the panel2 because I mentioned panel1 first in HTML. Same with panel3 and panel4.
My scenario is, I always want to display the panel below the visible panel. Is there any work around for this ?
<div> <asp:Panel ID="Panel1" runat="server" Visible="false"> </asp:Panel> <asp:Panel ID="Panel2" runat="server" Visible="false"> </asp:Panel> <asp:Panel ID="Panel3" runat="server" Visible="false"> </asp:Panel> <asp:Panel ID="Panel4" runat="server" Visible="false"> </asp:Panel> </div>