How to Style a cell in Gridview under ListView

How to Style a cell in Gridview under ListView

How to style every cell in Gridview.I want my cell text in a rounded text
box with red background.My code is
<ListView Margin="0" ItemsSource="{Binding ParamList}" >
<ListView.View >
<GridView >
<GridView.ColumnHeaderTemplate>
<DataTemplate>
<Border BorderThickness="2" CornerRadius="5"
Height="75" MinWidth="60" >
<Border.Background>Gray</Border.Background>
<TextBlock Foreground="WhiteSmoke" Margin="5"
Text="{Binding}" Width="Auto"
HorizontalAlignment="Center"
VerticalAlignment="Center" />
</Border>
</DataTemplate>
</GridView.ColumnHeaderTemplate>
<GridViewColumn Header="category1"
DisplayMemberBinding="{Binding Path=param1}" />
<GridViewColumn Header="category2"
DisplayMemberBinding="{Binding Path=param1}" />
</GridView>
</ListView.View>
</ListView>