ComboBox Background?

[RobDog888]

Ok so Im making my textboxes styled with a nice round shadowed look but when I apply it to the combox they round but dont apply the Background the same.

Anyone have any good styles or see what Im missing?

Thanks

<Border 
	Height="30" 
	Width="270"
	BorderBrush="White"
	HorizontalAlignment="Center"  
	BorderThickness="2" 
	CornerRadius="5" 
	Background="MintCream" 
	Grid.Row="4" 
	Grid.Column="1" 
	Margin="0">
	<Border.Effect>
		<DropShadowEffect Opacity="0.2"/>
	</Border.Effect>
	<ComboBox 
                 x:Name="cboRole" 
                 Margin="0" 
                 Height="30" 
                 FontSize="12" 
                 Grid.Row="4" 
                 Grid.Column="1" 
                 Background="MintCream"
                 HorizontalAlignment="Stretch" 
                 VerticalAlignment="Center"
                 BorderThickness="0"/>
</Border>