问基于下拉列表的选择值的CSS背景颜色

EN

<Asp:dropdownlist id="ddlColor"  runat="server">
<asp:ListItem Value="#00FFFF">Cyan</asp:ListItem>
<asp:ListItem Value="#FF00FF">Magenta</asp:ListItem
 </Asp:dropdownlist>

<Asp:dropdownlist id="ddlImages" runat="server" style="width: 275px">
 </Asp:dropdownlist>

 String[] Images = Directory.GetFiles(MapPath("~/Images/Layers/"), "*.png");
        for (int i = 0; i < Images.Length; i++)
            Images[i] = Path.GetFileNameWithoutExtension(Images[i]);
        ddlImages.DataSource = Images;
        ddlImages.DataBind();