Code

<Window.Resources>
<DataTemplate DataType="{x:Type vk:RegularKey}">
	<Grid x:Name="rootGrid">
		<Rectangle x:Name="rectangle" Fill="{DynamicResource IC_ButtonBackground}" Stroke="#FF393939" RadiusX="3" RadiusY="3">
			<Rectangle.Effect>
				<DropShadowEffect ShadowDepth="0" Opacity="0"/>
			</Rectangle.Effect>
		</Rectangle>
		<Rectangle x:Name="rectangle1" Stroke="#FF393939" RadiusX="3" RadiusY="3" Opacity="0">
			<Rectangle.Fill>
				<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
					<GradientStop Color="#99FFFFFF" Offset="0.009"/>
					<GradientStop Color="#19FFFFFF" Offset="1"/>
				</LinearGradientBrush>
			</Rectangle.Fill>
		</Rectangle>
		<Rectangle x:Name="rectangle1_Copy" RadiusX="3" Stroke="#72000000" StrokeThickness="2" RadiusY="3" Opacity="0">
			<Rectangle.Fill>
				<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
					<GradientStop Color="#19000000" Offset="0.991"/>
					<GradientStop Color="#19000000" Offset="0.009"/>
				</LinearGradientBrush>
			</Rectangle.Fill>
		</Rectangle>
		<Grid Background="Transparent" Margin="5">
			<TextBlock Text="{Binding CurrentCase}"
					   HorizontalAlignment="Center"
					   VerticalAlignment="Center" />
		</Grid>
	</Grid>
	<DataTemplate.Triggers>
		<Trigger Property="IsMouseOver" Value="True">
			<Setter Property="Opacity" TargetName="rectangle1" Value="1"/>
			<Setter Property="Effect" TargetName="rectangle">
				<Setter.Value>
					<DropShadowEffect Opacity="0.7" ShadowDepth="0"/>
				</Setter.Value>
			</Setter>

		</Trigger>
		<Trigger Property="IsMouseCaptured" Value="True">
			<Setter Property="Opacity" TargetName="rectangle1_Copy" Value="1"/>
			<Setter Property="Opacity" TargetName="rectangle1" Value="0"/>
			<Setter Property="Effect" TargetName="rectangle">
				<Setter.Value>
					<DropShadowEffect Opacity="0.7" ShadowDepth="0"/>
				</Setter.Value>
			</Setter>
		</Trigger>
	</DataTemplate.Triggers>
</DataTemplate>