aistudio-wpf-diagram/AIStudio.Wpf.DiagramDesigner/Styles/ScrollViewer.xaml

<ResourceDictionary 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" >

    <!-- SimpleStyles: ScrollViewer -->

    <Style x:Key="AIStudio.Diagram.Styles.ScrollViewer.Left" TargetType="{x:Type ScrollViewer}">
        <Setter Property="OverridesDefaultStyle" Value="True"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ScrollViewer}">
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="Auto"/>
                            <ColumnDefinition Width="*"/>
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition/>
                            <RowDefinition Height="Auto"/>
                        </Grid.RowDefinitions>

                        <ScrollContentPresenter Grid.Column="1"/>

                        <ScrollBar Name="PART_VerticalScrollBar"
              Value="{TemplateBinding VerticalOffset}"
              Maximum="{TemplateBinding ScrollableHeight}"
              ViewportSize="{TemplateBinding ViewportHeight}"
              Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}"/>
                        <ScrollBar Name="PART_HorizontalScrollBar"
              Orientation="Horizontal"
              Grid.Row="1"
              Grid.Column="1"
              Value="{TemplateBinding HorizontalOffset}"
              Maximum="{TemplateBinding ScrollableWidth}"
              ViewportSize="{TemplateBinding ViewportWidth}"
              Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}"/>

                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>