Version

Editing the CarouselPanelItem Template

In XAML:

<Style TargetType="{x:Type igw:CarouselPanelItem}">
        <Setter Property="Template">
          <Setter.Value>
            <ControlTemplate TargetType="{x:Type igw:CarouselPanelItem}">
              <Grid>
                <Grid.RowDefinitions>
                  <RowDefinition Height="*"/>
                  <RowDefinition Height="*"/>
                </Grid.RowDefinitions>
                <ScrollViewer x:Name="ScrollViewer" HorizontalScrollBarVisibility="{TemplateBinding ItemHorizontalScrollBarVisibility}" VerticalScrollBarVisibility="{TemplateBinding ItemVerticalScrollBarVisibility}">
                  <Viewbox HorizontalAlignment="Center" x:Name="ViewBox" VerticalAlignment="Bottom">
                    <Grid x:Name="itemContentHolder">
                      <Border x:Name="itemContentHolderBackground" Background="#00000000"
                              BorderBrush="Tomato" BorderThickness="1"/>
                      <ContentControl Margin="0,0,0,0" x:Name="itemContent" Content="{TemplateBinding Content}" ContentTemplate="{TemplateBinding ContentTemplate}"/>
                    </Grid>
                  </Viewbox>
                </ScrollViewer>
                <Canvas IsHitTestVisible=" Visibility="{Binding Path=ReflectionVisibility, RelativeSource={RelativeSource FindAncestor, AncestorLevel=1, AncestorType={x:Type igw:XamCarouselPanel}}}" Margin="0,2,0,0" Width="{Binding Path=ActualWidth, ElementName=ScrollViewer}" Height="{Binding Path=ActualHeight, ElementName=ScrollViewer}" Grid.Row="1">
                  <Canvas.OpacityMask>
                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                      <GradientStop Color="Tomato" Offset="0"/>
                      <GradientStop Color="#00000000" Offset="0.8"/>
                    </LinearGradientBrush>
                  </Canvas.OpacityMask>
                  <Canvas.Background>
                    <VisualBrush Opacity="0.3" AlignmentX="Center" AlignmentY="Bottom" Stretch="None" Visual="{Binding ElementName=ScrollViewer}">
                      <VisualBrush.RelativeTransform>
                        <TransformGroup>
                          <MatrixTransform Matrix="1,0,0,-1,0,0"/>
                          <TranslateTransform Y="1"/>
                        </TransformGroup>
                      </VisualBrush.RelativeTransform>
                    </VisualBrush>
                  </Canvas.Background>
                </Canvas>
              </Grid>
              <ControlTemplate.Triggers>
                <MultiTrigger>
                  <MultiTrigger.Conditions>
                    <Condition Property="IsFirstItem" Value="True"/>
                    <Condition Property="IsListContinuous" Value="True"/>
                  </MultiTrigger.Conditions>
                  <Setter Property="BorderThickness" TargetName="itemContentHolderBackground" Value="4,4,4,4"/>
                  <Setter Property="BorderBrush" TargetName="itemContentHolderBackground" Value="#FFFFFF00"/>
                  <Setter Property="Margin" TargetName="itemContent" Value="4,4,4,4"/>
                </MultiTrigger>
                <MultiTrigger>
                  <MultiTrigger.Conditions>
                    <Condition Property="IsLastItem" Value="True"/>
                    <Condition Property="IsListContinuous" Value="True"/>
                  </MultiTrigger.Conditions>
                  <Setter Property="BorderThickness" TargetName="itemContentHolderBackground" Value="4,4,4,4"/>
                  <Setter Property="BorderBrush" TargetName="itemContentHolderBackground" Value="#FF00FFFF"/>
                  <Setter Property="Margin" TargetName="itemContent" Value="4,4,4,4"/>
                </MultiTrigger>
                <Trigger Property="IsSelected" Value="True">
                  <Setter Property="Background" TargetName="itemContentHolderBackground">
                    <Setter.Value>
                      <LinearGradientBrush EndPoint="0,1" StartPoint="0,0">
                        <GradientStop Color="sc#1, 0.303573549, 0.303573549, 0.303573549" Offset="1"/>
                        <GradientStop Color="sc#1, 0.9095203, 0.9095203, 0.9095203" Offset="0"/>
                      </LinearGradientBrush>
                    </Setter.Value>
                  </Setter>
                  <Setter Property="Margin" TargetName="itemContent" Value="4,4,4,4"/>
                </Trigger>
                <Trigger Property="AutoScaleItemContentsToFit" Value="True">
                  <Setter Property="HorizontalScrollBarVisibility" TargetName="ScrollViewer" Value="Hidden"/>
                  <Setter Property="VerticalScrollBarVisibility" TargetName="ScrollViewer" Value="Hidden"/>
                  <Setter Property="Stretch" TargetName="ViewBox" Value="Uniform"/>
                  <Setter Property="StretchDirection" TargetName="ViewBox" Value="Both"/>
                  <Setter Property="Width" TargetName="ViewBox" Value="{Binding Path=ActualWidth, RelativeSource={RelativeSource FindAncestor, AncestorLevel=1, AncestorType={x:Type ScrollContentPresenter}}}"/>
                  <Setter Property="Height" TargetName="ViewBox" Value="{Binding Path=ActualHeight, RelativeSource={RelativeSource FindAncestor, AncestorLevel=1, AncestorType={x:Type ScrollContentPresenter}}}"/>
                </Trigger>
              </ControlTemplate.Triggers>
            </ControlTemplate>
          </Setter.Value>
        </Setter>
      </Style>