sourcegit/src/Views/Widgets/PopupPanel.xaml

<UserControl x:Class="SourceGit.Views.Widgets.PopupPanel"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:controls="clr-namespace:SourceGit.Views.Controls"
             mc:Ignorable="d" Visibility="Collapsed">
    <Grid ClipToBounds="True">
        <!-- Background to close -->
        <Border Background="Transparent" MouseLeftButtonDown="Cancel"/>
        
        <!-- Popup panel -->
        <Border
            Background="{StaticResource Brush.Popup}"
            BorderBrush="{StaticResource Brush.Border0}" 
            BorderThickness="1,0,1,1"
            HorizontalAlignment="Center"
            VerticalAlignment="Top"
            Width="500"
            Height="Auto">
            <Grid>                
                <!-- Custom panel -->
                <Border x:Name="body">
                    <StackPanel Margin="8" Orientation="Vertical">
                        <TextBlock Margin="8,8,0,18" x:Name="txtTitle" FontSize="18" FontWeight="DemiBold"/>
                        <ContentControl x:Name="container"/>
                        <StackPanel Margin="0,16,0,0" Height="32" Orientation="Horizontal" HorizontalAlignment="Right">
                            <Button Click="Sure" Width="80" Content="{StaticResource Text.Sure}" BorderBrush="{StaticResource Brush.FG1}" Background="{StaticResource Brush.Accent1}"/>
                            <Button Click="Cancel" Width="80" Margin="8,0,0,0" Content="{StaticResource Text.Cancel}"/>
                        </StackPanel>
                    </StackPanel>
                </Border>
                
                
                <!-- Progress mask -->
                <Border x:Name="mask" Visibility="Collapsed" Background="{StaticResource Brush.Popup}" Opacity=".9">
                    <StackPanel Orientation="Vertical" HorizontalAlignment="Center" VerticalAlignment="Center">
                        <controls:Loading x:Name="processing" Width="48" Height="48"/>
                        <TextBlock x:Name="txtMsg" Margin="0,16,0,0"/>
                    </StackPanel>
                </Border>
            </Grid>
        </Border>
    </Grid>
    
</UserControl>