radiobuttonlist style

i have a radio buttonlist like this :

<asp:RadioButtonList ID="RadioButtonList1" runat="server">
        <asp:ListItem>a</asp:ListItem>
        <asp:ListItem>b</asp:ListItem>
        <asp:ListItem>c</asp:ListItem>
    </asp:RadioButtonList>
,
but not like this :  <input name="radio" id="radio-1" type="radio"/>
how i can make style for it?
how i can use some  image as mask of each radiobutton?


thnx

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