Как связать значение свойства со свойством стиля в Blend 4?

Я создал шаблон стиля в Blend 4 для кнопки, но не знаю, как связать содержимое метки со свойством содержимого кнопки.

Вот стиль XAML:

<Style x:Key="NavButton" TargetType="Button">
    <Setter Property="Background" Value="#FF1F3B53"/>
    <Setter Property="Foreground" Value="#FF000000"/>
    <Setter Property="Padding" Value="3"/>
    <Setter Property="BorderThickness" Value="1"/>
    <Setter Property="BorderBrush">
        <Setter.Value>
            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                <GradientStop Color="#FFA3AEB9" Offset="0"/>
                <GradientStop Color="#FF8399A9" Offset="0.375"/>
                <GradientStop Color="#FF718597" Offset="0.375"/>
                <GradientStop Color="#FF617584" Offset="1"/>
            </LinearGradientBrush>
        </Setter.Value>
    </Setter>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="Button">
                <Grid>
                    <VisualStateManager.VisualStateGroups>
                        <VisualStateGroup x:Name="CommonStates">
                            <VisualState x:Name="Disabled"/>
                            <VisualState x:Name="Normal"/>
                            <VisualState x:Name="MouseOver"/>
                            <VisualState x:Name="Pressed"/>
                        </VisualStateGroup>
                    </VisualStateManager.VisualStateGroups>
                    <Rectangle Stroke="#FF0E1AD2" RadiusY="7" RadiusX="7" StrokeThickness="4">
                        <Rectangle.Fill>
                            <LinearGradientBrush EndPoint="0.517,1.07" StartPoint="0.511,0.001">
                                <GradientStop Color="#FF1828AB" Offset="1"/>
                                <GradientStop Color="#FFFBDEDE"/>
                            </LinearGradientBrush>
                        </Rectangle.Fill>
                    </Rectangle>
                    <Rectangle Margin="15,6,11,15" RadiusY="7" RadiusX="7" Stroke="#FF0E11D2" StrokeThickness="0">
                        <Rectangle.Fill>
                            <SolidColorBrush Color="White" Opacity="0.3"/>
                        </Rectangle.Fill>
                    </Rectangle>
                    <sdk:Label Margin="8" RenderTransformOrigin="1.567,-0.25" HorizontalContentAlignment="Center" Content="Button"/>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>