title: Border Animation wont change color
body: <p>I have created a check box using the XAML below, however for some reason I can't get the background color to change when the mouse goes over the control. The storyboard works for setting the opacity but the background color wont change. Any idea what I am doing wrong?</p>
  
  <pre><code>&lt;Style x:Key="{x:Type CheckBox}" TargetType="CheckBox"&gt;
      &lt;Setter Property="SnapsToDevicePixels" Value="true"/&gt;
      &lt;Setter Property="OverridesDefaultStyle" Value="true"/&gt;
      &lt;Setter Property="FocusVisualStyle" Value="{DynamicResource CheckBoxFocusVisual}" /&gt;
      &lt;Setter Property="Foreground" Value="{StaticResource FGBrush}"/&gt;
      &lt;Setter Property="HorizontalContentAlignment" Value="Stretch"/&gt;
      &lt;Setter Property="VerticalContentAlignment" Value="Stretch"/&gt;
      &lt;Setter Property="RenderOptions.EdgeMode" Value="Aliased"/&gt;
      &lt;Setter Property="Template"&gt;
          &lt;Setter.Value&gt;
              &lt;ControlTemplate TargetType="CheckBox"&gt;
                  &lt;BulletDecorator Background="Transparent" Height="20" MinHeight="{DynamicResource ResourceKey=MinimumIteractSizeDips}"&gt;
                      &lt;BulletDecorator.Bullet&gt;
                          &lt;Grid MinHeight="{DynamicResource ResourceKey=MinimumIteractSizeDips}"
                                MinWidth="{DynamicResource ResourceKey=MinimumIteractSizeDips}" 
                                Width="20"
                                Height="20"
                                SnapsToDevicePixels="True" RenderOptions.EdgeMode="Aliased" &gt;
  
                              &lt;Border x:Name="Border" 
                                      BitmapEffect="{StaticResource DropShadow}"
                                      CornerRadius="0" 
                                      Background="{StaticResource ControlGradientBrush}"
                                      BorderThickness="1"
                                      BorderBrush="{StaticResource NormalBorderBrush}" RenderOptions.EdgeMode="Aliased"
                                MinHeight="{DynamicResource ResourceKey=MinimumIteractSizeDips}"
                                MinWidth="{DynamicResource ResourceKey=MinimumIteractSizeDips}" 
                                Width="20"
                                Height="20" &gt;
  
                                  &lt;Viewbox Stretch="UniformToFill" Margin="2" &gt;
                                      &lt;Path 
                                      x:Name="CheckMark"
                                      SnapsToDevicePixels="True" 
                                      Stroke="{StaticResource GlyphBrush}"
                                      StrokeThickness="7"
                                      RenderOptions.EdgeMode="Aliased"
                                      Data="M 2 2 L 17 17 M 2 17 L 17 2" HorizontalAlignment="Center" VerticalAlignment="Center"/&gt;
                                  &lt;/Viewbox&gt;
  
                              &lt;/Border&gt;
                          &lt;/Grid&gt;
                      &lt;/BulletDecorator.Bullet&gt;
                      &lt;ContentPresenter Margin="4,0,0,0"
                              VerticalAlignment="Top"
                              HorizontalAlignment="Left"
                              RecognizesAccessKey="True"/&gt;
                  &lt;/BulletDecorator&gt;
                  &lt;ControlTemplate.Triggers&gt;
                      &lt;Trigger Property="IsChecked" Value="false"&gt;
                          &lt;Setter TargetName="CheckMark" Property="Visibility" Value="Collapsed"/&gt;
                      &lt;/Trigger&gt;
                      &lt;Trigger Property="IsChecked" Value="{x:Null}"&gt;
                          &lt;Setter TargetName="CheckMark" Property="Data" Value="M 0 7 L 7 0" /&gt;
                      &lt;/Trigger&gt;
                      &lt;Trigger Property="IsMouseOver" Value="true"&gt;
                          &lt;Trigger.EnterActions&gt;
                              &lt;BeginStoryboard Name="HighlightAnim"&gt;
                                  &lt;!--&lt;Storyboard TargetName="Border" TargetProperty="Opacity" &gt;
                                      &lt;DoubleAnimation To="0.5" Duration="00:00:00.1"/&gt;
                                  &lt;/Storyboard&gt;--&gt;
                                  &lt;Storyboard TargetName="Border"&gt;
                                      &lt;ColorAnimation Duration="0:0:0.15"
                                              Storyboard.TargetName="Border"
                                              Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)"
                                              To="Red" /&gt;
                                  &lt;/Storyboard&gt;
                              &lt;/BeginStoryboard&gt;
                          &lt;/Trigger.EnterActions&gt;
                          &lt;Trigger.ExitActions&gt;
                              &lt;StopStoryboard BeginStoryboardName="HighlightAnim"/&gt;
                          &lt;/Trigger.ExitActions&gt;
                      &lt;/Trigger&gt;
                      &lt;Trigger Property="IsPressed" Value="true"&gt;
                          &lt;Setter TargetName="Border" Property="Background" Value="{StaticResource PressedBrush}" /&gt;
                          &lt;Setter TargetName="Border" Property="BorderBrush" Value="{StaticResource PressedBorderBrush}" /&gt;
                      &lt;/Trigger&gt;
                      &lt;Trigger Property="IsEnabled" Value="false"&gt;
                          &lt;Setter TargetName="Border" Property="Background" Value="{StaticResource DisabledBackgroundBrush}" /&gt;
                          &lt;Setter TargetName="Border" Property="BorderBrush" Value="{StaticResource DisabledBorderBrush}" /&gt;
                          &lt;Setter Property="Foreground" Value="{StaticResource DisabledForegroundBrush}"/&gt;
                      &lt;/Trigger&gt;
                  &lt;/ControlTemplate.Triggers&gt;
              &lt;/ControlTemplate&gt;
          &lt;/Setter.Value&gt;
      &lt;/Setter&gt;
  &lt;/Style&gt;
  </code></pre>