Создать свой стиль для неактивного TextBox

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    x:Class="Rout.Task"
    x:Name="UserControl" Height="24.333" Width="300">
    <UserControl.Resources>
        <Style x:Key="ControlStyle1" TargetType="{x:Type TextBox}">
            <Style.Triggers>
                <Trigger Property="IsEnabled" Value="False">
                    <Setter Property="Background" Value="{x:Null}"/>
                    <Setter Property="BorderBrush" Value="{x:Null}"/>
                    <Setter Property="Foreground" Value="Silver"/>
                    <Setter Property="CaretBrush" Value="#FFDADADA"/>
                </Trigger>
            </Style.Triggers>
        </Style>
    </UserControl.Resources>
    <Grid x:Name="LayoutRoot" Margin="0">
        <Grid.Background>
            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                <GradientStop Color="#FF3F3F3F" Offset="0"/>
                <GradientStop Color="#FF3B3B3B" Offset="1"/>
                <GradientStop Color="#FF1B1B1B" Offset="0.524"/>
            </LinearGradientBrush>
        </Grid.Background>
        <TextBox x:Name="u_TODO_Text" Margin="16.995,1.666,45.452,2.666" TextWrapping="Wrap" Text="TextBox" Height="20" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="Silver" CaretBrush="#FFDADADA" Style="{StaticResource ControlStyle1}"/>
    </Grid>
</UserControl>