Input.xaml

<Window 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" 
    SizeToContent="WidthAndHeight"
    MinWidth = "900"
    MinHeight = "150"
    FontFamily="Consolas" 
    FontSize="14"
    FocusManager.FocusedElement="{Binding ElementName=Value}"
    Topmost="True">
    <Window.Resources>
        <Style TargetType="Control" x:Key="Margin">
            <Setter Property="Margin" Value="5" />
        </Style>
        <Style TargetType="Button" BasedOn="{StaticResource Margin}">
            <Setter Property="Background" Value="LightBlue" />
            <Setter Property="Height" Value="30" />
            <Setter Property="Width" Value="100" />
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border 
                            CornerRadius="5" 
                            BorderThickness="1"
                            Background="{TemplateBinding Background}">
                            <ContentPresenter 
                                Content="{TemplateBinding Content}"
                                HorizontalAlignment="Center"
                                VerticalAlignment="Center" />
                        </Border>                                
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="Background" Value="Cyan" />
                </Trigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto" />
            <ColumnDefinition Width="Auto" />
            <ColumnDefinition Width="Auto" />
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="1*" />
            <RowDefinition Height="2*" />
        </Grid.RowDefinitions>
        <TextBlock Name="Prompt" Grid.ColumnSpan="3" Margin="5" />
        <TextBox 
            Grid.Row="1" 
            Name="Value" 
            Style="{StaticResource Margin}"
            MaxLines="6"
            AcceptsReturn="True" 
            SpellCheck.IsEnabled="True" 
            Language="en-US"
            Width="600" 
            ScrollViewer.HorizontalScrollBarVisibility="Auto"
            ScrollViewer.VerticalScrollBarVisibility="Auto"/>
        <Button 
            Name="OK" 
            Grid.Row="1" 
            Grid.Column="1">
            <AccessText>
                _OK
            </AccessText>
        </Button>
        <Button 
            Name="Cancel"
            Grid.Row="1" 
            Grid.Column="2">
            <AccessText>
                _Cancel
            </AccessText>
        </Button>
    </Grid>
</Window>