Dropdown font color in c#.net

HI all,
i am using dropdown list.in code behind i am inserting the data in dropdown item(0) "dropdown.items.insert(0,"select") .Inserts perfectly.Issue is i am adding color for the item(0) dropdown.items(0).attributes.add("style","color:gray") . the dropdown is highligted perfectly.But before expand of the dropdown the text "select" should display gray (working fine in IE but in other browser it's display black color,when we expand the dropdown i can see the grayed color item).