Hi,
You can use different css in a GridView for changing style of its different parts like Rows, AlternateRow, Header, Footer etc
<asp:gridview id="GridView1" xmlns:asp="#unknown">
runat="server"
ShowFooter="true"
AutoGenerateColumns="false"
DataSourceID="SqlDataSource1"
CssClass=""
RowStyle-CssClass=""
AlternatingRowStyle-CssClass=""
HeaderStyle-CssClass=""
FooterStyle-CssClass="">
</asp:gridview>