Menu background clour

i have my menu items like below
<items>
<asp:menuitems text="abc" value="abc"></asp;menuitem>
<asp:menuitems text="def" value="def"></asp;menuitem>
<asp:menuitems text="ghi" value="ghi"></asp;menuitem>
</items>

how to set 3 different back ground colours to 3 different menu items...



Please help me