styling listitems in radiobuttonlist control or checkboxlist control

for the radiobuttonlist control, when I try to style individual buttons with 'span'
I get a error, is there some way to style each button? <asp:RadioButtonList ID="beginBasic" runat="server" AutoPostBack="false" TextAlign="Right" > <asp:listItem Value="button1" Text="button 1 text" > </asp:listItem> <span class="greenFont01"> <asp:listItem Value="button2" Text="button 2 text" > </asp:listItem> </span> </asp:RadioButtonList> error is: System.Web.UI.WebControls.ListItemCollection must have items of type 'System.Web.UI.WebControls.ListItem'. 'span' is of type 'System.Web.UI.HtmlControls.HtmlGenericControl
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