代码块：
<DataGrid AutoGenerateColumns="False" Margin="5"
ColumnHeaderHeight="30" RowHeight="30"
VerticalAlignment="Stretch"
VerticalContentAlignment="Stretch"
Height="Auto"
Background="#B3FFFFFF"
ScrollViewer.VerticalScrollBarVisibility="Auto"
CanUserAddRows="False"
HeadersVisibility="Column"
Opacity="1" HorizontalContentAlignment="Center"
CanUserReorderColumns="True" MouseDoubleClick="DataGrid_MouseDoubleClick"
IsReadOnly="True" >
<DataGrid.RowStyle>
<Style TargetType="DataGridRow" BasedOn="{StaticResource DataGridRowStyle}">
<Style.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected" Value="True"/>
<Condition Property="Selector.IsSelectionActive" Value="False"/>
</MultiTrigger.Conditions>
<MultiTrigger.Setters>
<Setter Property="Background" Value="#6066CCFF"/>
</MultiTrigger.Setters>
</MultiTrigger>
</Style.Triggers>
</Style>
</DataGrid.RowStyle>
<DataGrid.DataContext>
<local:Student/>
</DataGrid.DataContext>
<DataGrid.Columns>
<DataGridTextColumn Header="姓名" Binding="{Binding studentName}" Width="80"/>
<DataGridTextColumn Header="民族" Binding="{Binding studentNation}" Width="60"/>
<DataGridTextColumn Header="注册时间" Binding="{Binding regDate}" Width="80"/>
<DataGridTextColumn Header="身份证号" Binding="{Binding personalId}" Width="160"/>
<DataGridTextColumn Header="住址" Binding="{Binding address}" Width="*"/>
<DataGridTextColumn Header="联系方式" Binding="{Binding telephoneNumber}" Width="120"/>
<DataGridCheckBoxColumn Header="是否注册志愿者" Binding="{Binding volunteerState}" Width="110" CellStyle="{Binding Source={StaticResource DataGridComboBoxCenterColumnStyle}}"/>
</DataGrid.Columns>
<DataGrid.Items>
<local:Student studentName="name" personalId="360802" address="江西省吉安市吉州区白鹭洲中学高二三班" telephoneNumber="183775"/>
<local:Student studentName="name" personalId="360802" address="江西省吉安市吉州区白鹭洲中学高二三班" telephoneNumber="183706"/>
</DataGrid.Items>
</DataGrid>
问题截图：
如图，选中行在DataGrid失去焦点后会显示设置的背景色，但是会被单元格的样式遮挡，单独设置过单元格样式但是没办法正确设置颜色，故此求助
