如何在WPF中更改ScrollBar的样式

<Style x:Key="CustomScrollBarStyle" TargetType="{x:Type ScrollBar}">
    <Setter Property="Background" Value="LightGray"/>
    <Setter Property="BorderBrush" Value="Gray"/>
    <Setter Property="BorderThickness" Value="1"/>
    <Setter Property="Width" Value="10"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ScrollBar}">
                <Grid>
                    <Border Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            CornerRadius="5"/>
                    <Track x:Name="PART_Track" 
                           IsDirectionReversed="True">
                        <Track.DecreaseRepeatButton>
                            <RepeatButton Command="ScrollBar.PageUpCommand"
                                          Opacity="0"/>
                        </Track.DecreaseRepeatButton>
                        <Track.IncreaseRepeatButton>
                            <RepeatButton Command="ScrollBar.PageDownCommand"
                                          Opacity="0"/>
                        </Track.IncreaseRepeatButton>
                        <Track.Thumb>
                            <Thumb Background="DarkGray"
                                   BorderBrush="Gray"
                                   BorderThickness="1"
                                   Width="8"/>
                        </Track.Thumb>
                    </Track>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<ScrollBar Style="{StaticResource CustomScrollBarStyle}" />