<Border xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Margin="30" CornerRadius="10" Background="Gray">
        <Grid>
            <Rectangle Width="6" Height="28">
                <Rectangle.Fill>
                    <SolidColorBrush x:Name="Brush1" Color="White" />
                </Rectangle.Fill>
            </Rectangle>
            <Rectangle  Width="28" Height="6"  >
                <Rectangle.Fill>
                    <SolidColorBrush x:Name="Brush2" Color="White" />
                </Rectangle.Fill>
            </Rectangle>
        </Grid>
        <Border.Triggers>
            <EventTrigger RoutedEvent="Border.MouseEnter">
                <BeginStoryboard>
                    <Storyboard>
                        <ColorAnimation
                Storyboard.TargetName="Brush1"
                Storyboard.TargetProperty="Color"
                To="LightSeaGreen" Duration="0:0:0.15" />
                        <ColorAnimation
                Storyboard.TargetName="Brush2"
                Storyboard.TargetProperty="Color"
                To="LightSeaGreen" Duration="0:0:0.15" />
                    </Storyboard>
                </BeginStoryboard>
            </EventTrigger>
            <EventTrigger RoutedEvent="Border.MouseLeave">
                <BeginStoryboard>
                    <Storyboard>
                        <ColorAnimation
                Storyboard.TargetName="Brush1"
                Storyboard.TargetProperty="Color"
                To="White" Duration="0:0:0.15" />
                        <ColorAnimation
                Storyboard.TargetName="Brush2"
                Storyboard.TargetProperty="Color"
                To="White" Duration="0:0:0.15" />
                    </Storyboard>
                </BeginStoryboard>
            </EventTrigger>
        </Border.Triggers>
    </Border>