WPF自訂一個MessageBox

WPF的MessageBox太醜了，自己定義了一個。

這是效果：

 

XAML:

<Window x:Class="AgileToDo.UMessageBox"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="UMessageBox" Height="130" Width="280" WindowStyle="None"   Background="{x:Null}"  
        ResizeMode="NoResize"  x:Name="main"
        AllowsTransparency="True" WindowStartupLocation="CenterScreen">
    <Window.Triggers>
        <EventTrigger RoutedEvent="Window.Loaded" >
            <BeginStoryboard>
                <Storyboard Name="sbOpShow">
                    <DoubleAnimation
                    Storyboard.TargetName="main" 
                    Storyboard.TargetProperty="Opacity" 
                    From="0" To="0.8" Duration="0:0:0.15"/>
                </Storyboard>
            </BeginStoryboard>
        </EventTrigger>
    </Window.Triggers>
    <Window.Resources>
    </Window.Resources>

    <Border Background="#F03A3A3A" Opacity="1" CornerRadius="3">
            <Canvas>
                
            <Border Canvas.Top="0" Height="25" Width="{Binding ElementName=main, Path=Width,UpdateSourceTrigger=PropertyChanged}" 
                    BorderThickness="0,0,0,1" BorderBrush="#FFEFE2E2">
                <TextBlock x:Name="lblTitle" Text="test" HorizontalAlignment="Left"