How to control alternativing color via CSS in AccordianPane?

I'm using an Accordion control. For each item inside of a pane, I like to have alternating background. How do I control this background color via CSS? Below is my pane code.

<asp:AccordionPane ID="adp2000s" runat="server"><Header>
                            2000s</Header><Content><asp:SqlDataSource ID="sql2000s" runat="server"
                                ConnectionString="<%$ ConnectionStrings:ConnStr %>"
                                SelectCommand="SELECT [clsNoteID], [fstName], [lstName], [mdnName], [classOf1], [classOf2], [major1], [major2], [notes], [dateInsert] FROM [classNotes] WHERE (([approval] = @approval) AND ([archived] = @archived) AND ([cateID] = @cateID) AND ([classOf1] &gt;= @classOf1) AND ([classOf1] &lt; @classOf12)) ORDER BY [classOf1], [classOf2], [lstName]"><SelectParameters><asp:Parameter DefaultValue="True" Name="approval" Type="Boolean" /><asp:Parameter DefaultValue="False" Name="archived" Type="Boolean" /><asp:Parameter DefaultValue="1" Name="cateID" Type="Int32" /><asp:Parameter DefaultValue="2000" Name="classOf1" Type="Int32" /><asp:Parameter DefaultValue="2010" Name="classOf12" Type="Int32" /></SelectParameters></asp:SqlDataSource><asp:Accordion
                                ID="acd2000s"
                                runat="Server"
                                SelectedIndex="0"
                                HeaderCssClass="accordionHeader"
                                ContentCssClass="accordionContent"
                                AutoSize="None"
                                FadeTransitions="true"
                                TransitionDuration="250"
                                FramesPerSecond="40"
                                DataSourceID="sql2000s"><Panes></Panes><HeaderTemplate><asp:Label ID="lblFullName" runat="server" Text='<%# getName() %>' /></HeaderTemplate><ContentTemplate><asp:Label ID="lblClassNews" runat="server" Text='<%# getClassNews() %>' /></ContentTemplate></asp:Accordion></Content></asp:AccordionPane>