ConfirmationDialog.xaml

<Window x:Class="DotNetPad.ConfirmationDialog"
        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"
        xmlns:local="clr-namespace:DotNetPad"
        mc:Ignorable="d" WindowStartupLocation="CenterOwner"
        ShowInTaskbar="False" ResizeMode="CanResize" WindowStyle="None" Loaded="Window_Loaded"
        SizeToContent="WidthAndHeight" BorderThickness="0" Background="Transparent">
    <Grid HorizontalAlignment="Stretch" VerticalAlignment="Center">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <Grid Grid.Row="0" Name="TopGrid" HorizontalAlignment="Stretch" VerticalAlignment="Center">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="25" />
                <ColumnDefinition Width="*" MaxWidth="700" />
            <ColumnDefinition Width="25" />
            </Grid.ColumnDefinitions>
            <Grid Grid.Column="1" HorizontalAlignment="Stretch" VerticalAlignment="Center">
                <Grid.RowDefinitions>
                    <RowDefinition Height="Auto" />
                    <RowDefinition Height="Auto" />
                </Grid.RowDefinitions>
                <TextBlock Grid.Row="0" Height="Auto" Text=".NETpad" 
                                   Style="{DynamicResource SubtitleTextBlockStyle}" 
                                   Margin="0,25,0,10" />
                <TextBlock Grid.Row="1" Name="ConfirmTextBlock" Text="Do you want to save the changes to Untitled.txt?" 
                                   Style="{DynamicResource BodyTextBlockStyle}" Margin="0,0,10,0" />
            </Grid>
        </Grid>
        <Border Grid.Row="1" Name="BottomBorder" BorderThickness="0,1,0,0" 
                    HorizontalAlignment="Stretch" VerticalAlignment="Top" Margin="0,25,0,0"
                    BorderBrush="{DynamicResource DividerStrokeColorDefaultBrush}"
                    Background="{DynamicResource LayerOnMicaBaseAltFillColorSecondaryBrush}" >
            <Grid Height="Auto" VerticalAlignment="Center" HorizontalAlignment="Stretch">
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="25" />
                    <ColumnDefinition Width="*" MinWidth="100" MaxWidth="700" />
                    <ColumnDefinition Width="25" />
                </Grid.ColumnDefinitions>
                <Grid Grid.Column="1" Name="ButtonGrid" HorizontalAlignment="Stretch" VerticalAlignment="Center">
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition MaxWidth="300" Width="*" />
                        <ColumnDefinition MaxWidth="300" Width="*" />
                        <ColumnDefinition MaxWidth="300" Width="*" />
                    </Grid.ColumnDefinitions>
                    <Button Grid.Column="0" Content="Save" MinWidth="90" Height="32" MinHeight="32" Focusable="True" 
                                HorizontalAlignment="Stretch" Margin="0,20,10,20" Name="ConfirmationSaveButton" Click="ConfirmationButton_Click"
                                TabIndex="0" IsDefault="True"
                                Style="{DynamicResource AccentButtonStyle}" />
                    <Button Grid.Column="1" Content="Don't save" MinWidth="90" Height="32" MinHeight="32" 
                                HorizontalAlignment="Stretch" TabIndex="1" 
                                Margin="0,20,0,20" Name="ConfirmationDontSaveButton" Focusable="True" Click="ConfirmationButton_Click" />
                    <Button Grid.Column="2" Content="Cancel" MinWidth="90" Height="32" MinHeight="32" 
                                HorizontalAlignment="Stretch" IsCancel="true" TabIndex="2" 
                                Margin="10,20,0,20" Name="ConfirmationCancelButton" Focusable="True" Click="ConfirmationButton_Click" />
                </Grid>
            </Grid>
        </Border>
    </Grid>
</Window>