how to change style of DDL

I just want to change the style of Dropdownlist(eg.Change the border style)in my asp.net application.how can i edit my style sheet to do this. Thanks

Step1: First assign the Css class to ddl

 

<asp:dropdownlist id="ddlTest" runat="server" CssClass="MyCssClass">
  &nb

Step1: First assign the Css class to ddl

 

<asp:dropdownlist id="ddlTest" runat="server" CssClass="MyCssClass">
  &nb

Hello dbbatagoda thanks for your quick reply.yes it's true, it change the fonts and width and other properties.but still it don't have flat style.cas still it looks 3d.so what i want is to have a flat