ColorAnimation颜色错误

WPF新手，问问各位大佬：
我的代码是这样的
<Style x:Key="styleButtonClose" TargetType="Button">
<Setter Property="Width" Value="39"/>
<Setter Property="Height" Value="39"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="BorderThickness" Value="0"/>
<Setter Property="Focusable" Value="False"/>
<Style.Triggers>
<EventTrigger RoutedEvent="MouseEnter">
<BeginStoryboard>
<Storyboard>
<ColorAnimation Storyboard.TargetProperty="Background.Color" From="Transparent" To="#EA3447" Duration="0:0:1"/>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<EventTrigger RoutedEvent="MouseLeave">
<BeginStoryboard>
<Storyboard>
<ColorAnimation Storyboard.TargetProperty="Background.Color" From="#EA3447" To="Transparent" Duration="0:0:1"/>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Style.Triggers>
</Style>
理论上来说，MouseEnter时这个按钮的颜色应该是红色（#EA3447），结果却是这样：

但是在MouseLeave时就突然变红，然后动画正常进行
求求了大佬们