How to apply css for dropdownList in MVC .net?

First, I have created a controller using entity framework but the generated result was not in the appropriate form. So, I applied Css class and header name for the DropdownList. 

Following code is generated automatically, 

@Html.DropDownList("DepartmentId", String.Empty)

 I have created a css class with style property and apply to dropdrownlist. 

<style type="text/css">
    mydrowpdownstyle {
        background-color: blue;
        color:white;
    }
</style> 

Solution: 

@Html.DropDownList("Category", null, "Select Category", new { Class = "mydrowpdownstyle" })