title: Color transition in a button's hover effect using a style in WPF
body: <p>I just recently started in WPF and I'm trying to replace the default hover effect of a buttton using a style I made.</p>
  
  <pre><code>&lt;Style x:Key="UserType_LoginButton" TargetType="Button"&gt;
      &lt;Setter Property="OverridesDefaultStyle" Value="True"/&gt;
      &lt;Setter Property="Template"&gt;
          &lt;Setter.Value&gt;
              &lt;ControlTemplate TargetType="Button"&gt;
                  &lt;Border Name="border"
                      BorderBrush="{TemplateBinding BorderBrush}"
                      Background="{TemplateBinding Background}"&gt;
                      &lt;ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/&gt;
                  &lt;/Border&gt;
                  &lt;ControlTemplate.Triggers&gt;
                      &lt;Trigger Property="IsMouseOver" Value="True"&gt;
                          &lt;Setter TargetName="border" Property="BorderBrush" Value="{Binding BorderBrush}"/&gt;
                      &lt;/Trigger&gt;
                  &lt;/ControlTemplate.Triggers&gt;
              &lt;/ControlTemplate&gt;
          &lt;/Setter.Value&gt;
      &lt;/Setter&gt;
      &lt;EventTrigger RoutedEvent="Button.Click"&gt;
          &lt;BeginStoryboard&gt;
              &lt;Storyboard&gt;
                  &lt;ColorAnimation  Storyboard.TargetName="BackgroundGrid" From="Red" To="Blue" Duration="0:0:4" Storyboard.TargetProperty="Background" /&gt;
              &lt;/Storyboard&gt;
          &lt;/BeginStoryboard&gt;
      &lt;/EventTrigger&gt;
  &lt;/Style&gt;
  </code></pre>
  
  <p>Unfortunately, I get the error:</p>
  
  <pre><code>A value of type 'Event Trigger' cannot be added to a collection or dictionary of type 'SetterBaseCollection'
  </code></pre>
  
  <p>How can I add the event trigger then?</p>