ScrollBar.xaml

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

    <SolidColorBrush x:Key="StandardBorderBrush"
                 Color="#888" />
    <SolidColorBrush x:Key="StandardBackgroundBrush"
                 Color="Black" />
    <SolidColorBrush x:Key="HoverBorderBrush"
                 Color="#DDD" />
    <SolidColorBrush x:Key="SelectedBackgroundBrush"
                 Color="Gray" />
    <SolidColorBrush x:Key="SelectedForegroundBrush"
                 Color="White" />
    <SolidColorBrush x:Key="DisabledForegroundBrush"
                 Color="#888" />
    <SolidColorBrush x:Key="GlyphBrush"
                 Color="#444" />
    <SolidColorBrush x:Key="NormalBrush"
                 Color="#888" />
    <SolidColorBrush x:Key="NormalBorderBrush"
                 Color="#888" />
    <SolidColorBrush x:Key="HorizontalNormalBrush"
                 Color="#C8C8C8" />
    <SolidColorBrush x:Key="HorizontalNormalBorderBrush"
                 Color="#888" />

    <Style x:Key="ScrollBarLineButton"
       TargetType="{x:Type RepeatButton}">
        <Setter Property="Visibility"
            Value="Hidden" />
        <Setter Property="SnapsToDevicePixels"
            Value="True" />
        <Setter Property="OverridesDefaultStyle"
            Value="true" />
        <Setter Property="Focusable"
            Value="false" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type RepeatButton}">
                    <Border Name="Border"
                        Margin="1"
                        CornerRadius="2"
                        Background="{StaticResource NormalBrush}"
                        BorderBrush="{StaticResource NormalBorderBrush}"
                        BorderThickness="1">
                        <Path HorizontalAlignment="Center"
                          VerticalAlignment="Center"
                          Fill="{StaticResource GlyphBrush}"
                          Data="{Binding Path=Content, RelativeSource={RelativeSource TemplatedParent}}" />
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsPressed"
                             Value="true">
                            <Setter TargetName="Border"
                                Property="Background"
                                Value="{StaticResource SelectedForegroundBrush}" />
                        </Trigger>
                        <Trigger Property="IsEnabled"
                             Value="false">
                            <Setter Property="Foreground"
                                Value="{StaticResource DisabledForegroundBrush}" />
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="ScrollBarPageButton"
       TargetType="{x:Type RepeatButton}">
        <Setter Property="Visibility"
            Value="Hidden" />
        <Setter Property="SnapsToDevicePixels"
            Value="True" />
        <Setter Property="OverridesDefaultStyle"
            Value="true" />
        <Setter Property="IsTabStop"
            Value="false" />
        <Setter Property="Focusable"
            Value="false" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type RepeatButton}">
                    <Border Background="Black" />
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

    <Style x:Key="ScrollBarThumb"
       TargetType="{x:Type Thumb}">
        <Setter Property="SnapsToDevicePixels"
            Value="True" />
        <Setter Property="OverridesDefaultStyle"
            Value="true" />
        <Setter Property="IsTabStop"
            Value="false" />
        <Setter Property="Focusable"
            Value="false" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Thumb}">
                    <Border CornerRadius="4"
                        Background="{TemplateBinding Background}"
                        BorderBrush="{TemplateBinding BorderBrush}"
                        BorderThickness="0"
                        Width="6"
                        Margin="1,0,1,0" />
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

    <ControlTemplate x:Key="VerticalScrollBar"
                 TargetType="{x:Type ScrollBar}">
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition MaxHeight="0" />
                <RowDefinition Height="0.00001*" />
                <RowDefinition MaxHeight="0" />
            </Grid.RowDefinitions>
            <Border Grid.RowSpan="3"
                CornerRadius="2"
                Background="Transparent" />
            <RepeatButton Grid.Row="0"
                      Style="{StaticResource ScrollBarLineButton}"
                      Height="18"
                      Command="ScrollBar.LineUpCommand"
                      Content="M 0 4 L 8 4 L 4 0 Z" />
            <Track Name="PART_Track"
               Grid.Row="1"
               IsDirectionReversed="true">
                <Track.DecreaseRepeatButton>
                    <RepeatButton Style="{StaticResource ScrollBarPageButton}"
                              Command="ScrollBar.PageUpCommand" />
                </Track.DecreaseRepeatButton>
                <Track.Thumb>
                    <Thumb Style="{StaticResource ScrollBarThumb}"
                       Margin="1,0,1,0"
                       Background="{StaticResource HorizontalNormalBrush}"
                       BorderBrush="{StaticResource HorizontalNormalBorderBrush}" />
                </Track.Thumb>
                <Track.IncreaseRepeatButton>
                    <RepeatButton Style="{StaticResource ScrollBarPageButton}"
                              Command="ScrollBar.PageDownCommand" />
                </Track.IncreaseRepeatButton>
            </Track>
            <RepeatButton Grid.Row="3"
                      Style="{StaticResource ScrollBarLineButton}"
                      Height="18"
                      Command="ScrollBar.LineDownCommand"
                      Content="M 0 0 L 4 4 L 8 0 Z" />
        </Grid>
    </ControlTemplate>

    <Style x:Key="{x:Type ScrollBar}"
       TargetType="{x:Type ScrollBar}">
        <Setter Property="SnapsToDevicePixels"
            Value="True" />
        <Setter Property="OverridesDefaultStyle"
            Value="true" />
        <Style.Triggers>
            <Trigger Property="Orientation"
                 Value="Vertical">
                <Setter Property="Width"
                    Value="10" />
                <Setter Property="Height"
                    Value="Auto" />
                <Setter Property="Template"
                    Value="{StaticResource VerticalScrollBar}" />
            </Trigger>
        </Style.Triggers>
    </Style>

    <Style x:Key="FavsScrollViewer"
       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 />
                        </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}" />

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

    <Style TargetType="{x:Type ScrollViewer}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ScrollViewer}">
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition />
                            <ColumnDefinition Width="Auto" />
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition />
                            <RowDefinition Height="Auto" />
                        </Grid.RowDefinitions>
                        <ScrollContentPresenter Grid.Column="0" />
                        <ScrollBar x:Name="PART_VerticalScrollBar"
                               Grid.Row="0"
                               Grid.Column="1"
                               Value="{TemplateBinding VerticalOffset}"
                               Maximum="{TemplateBinding ScrollableHeight}"
                               ViewportSize="{TemplateBinding ViewportHeight}"
                               Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}" />
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>