MainWindow.xaml

<Window x:Class="InstallPilot.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="InstallPilot" Height="720" Width="1120"
        MinWidth="880" MinHeight="580"
        WindowStartupLocation="CenterScreen"
        Background="{DynamicResource bgBrush}">
    
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="240"/>
            <ColumnDefinition Width="1"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>

        <!-- Left Sidebar Navigation -->
        <Border Grid.Column="0" Background="{DynamicResource sidebarBrush}">
            <Grid>
                <Grid.RowDefinitions>
                    <RowDefinition Height="68"/>
                    <RowDefinition Height="Auto"/>
                    <RowDefinition Height="*"/>
                    <RowDefinition Height="Auto"/>
                </Grid.RowDefinitions>

                <!-- Sidebar Logo & Header -->
                <Grid Grid.Row="0" Margin="20,0,8,0">
                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                        <!-- Application Logo -->
                        <Grid Margin="0,0,10,0" Width="28" Height="28">
                            <Ellipse x:Name="LogoFallbackCircle" Width="28" Height="28" Fill="{DynamicResource accentBrush}"/>
                            <Image x:Name="ImgLogo" Width="28" Height="28" Stretch="Uniform" Visibility="Collapsed"/>
                        </Grid>
                        <TextBlock Text="InstallPilot" FontFamily="Segoe UI" FontSize="16" FontWeight="Bold" Foreground="{DynamicResource fgBrush}" VerticalAlignment="Center"/>
                    </StackPanel>
                </Grid>

                <!-- Search Input -->
                <Grid Grid.Row="1" Margin="12,0,12,8">
                    <TextBox x:Name="TxtSearch" TextChanged="TxtSearch_TextChanged" Height="32"/>
                    <TextBlock x:Name="TxtSearchPlaceholder" IsHitTestVisible="False" Text="Rechercher..." VerticalAlignment="Center" HorizontalAlignment="Left" Margin="12,0,0,0" Foreground="{DynamicResource fg3Brush}" FontSize="11" FontFamily="Segoe UI"/>
                </Grid>

                <!-- Navigation List -->
                <ScrollViewer Grid.Row="2" VerticalScrollBarVisibility="Auto">
                    <StackPanel x:Name="StackNav" Margin="8,0"/>
                </ScrollViewer>

                <!-- Sidebar Preferences Button -->
                <Border Grid.Row="3" BorderBrush="{DynamicResource borderBrush}" BorderThickness="0,1,0,0" Padding="12,10,12,14">
                    <Button x:Name="BtnPrefs" Content="Préférences" Height="36" Click="BtnPrefs_Click"/>
                </Border>
            </Grid>
        </Border>

        <!-- Sidebar Divider -->
        <Border Grid.Column="1" Background="{DynamicResource borderBrush}"/>

        <!-- Main Content Area -->
        <Grid Grid.Column="2">
            <Grid.RowDefinitions>
                <RowDefinition Height="80"/>
                <RowDefinition Height="1"/>
                <RowDefinition Height="*"/>
                <RowDefinition Height="1"/>
                <RowDefinition Height="68"/>
            </Grid.RowDefinitions>

            <!-- Main Content Header -->
            <Grid Grid.Row="0" Margin="28,10,28,0">
                <StackPanel VerticalAlignment="Center">
                    <TextBlock x:Name="TxtPageTitle" Text="Choisissez les applications" FontFamily="Segoe UI" FontSize="20" FontWeight="Bold" Foreground="{DynamicResource fgBrush}"/>
                    <TextBlock x:Name="TxtPageSubtitle" Text="Sélectionnez des applications puis cliquez sur « Obtenir votre sélection »." FontFamily="Segoe UI" FontSize="11" Foreground="{DynamicResource fg2Brush}" Margin="0,2,0,0"/>
                </StackPanel>

                <!-- Global Select Link & Selected counter -->
                <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" VerticalAlignment="Center">
                    <TextBlock x:Name="BtnGlobalToggleAll" Text="tout" FontFamily="Segoe UI" FontSize="11" TextDecorations="Underline" Foreground="{DynamicResource accentBrush}" Cursor="Hand" MouseLeftButtonDown="BtnGlobalToggleAll_MouseLeftButtonDown"/>
                    <TextBlock x:Name="TxtGlobalCounter" Text="" FontFamily="Segoe UI" FontSize="11" Foreground="{DynamicResource accentBrush}" Margin="12,0,0,0"/>
                </StackPanel>
            </Grid>

            <!-- Divider -->
            <Border Grid.Row="1" Background="{DynamicResource borderBrush}"/>

            <!-- Scrollable Content Grid -->
            <ScrollViewer Grid.Row="2" VerticalScrollBarVisibility="Auto">
                <StackPanel x:Name="StackContent" Margin="24,16,24,16"/>
            </ScrollViewer>

            <!-- Divider -->
            <Border Grid.Row="3" Background="{DynamicResource borderBrush}"/>

            <!-- Main Footer Pane -->
            <Border Grid.Row="4" Background="{DynamicResource surfaceBrush}">
                <Grid Margin="24,0">
                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center" HorizontalAlignment="Left">
                        <TextBlock x:Name="TxtFooterVersion" Text="InstallPilot v2.0" FontFamily="Segoe UI" FontSize="10" FontWeight="Bold" Foreground="{DynamicResource fg3Brush}" VerticalAlignment="Center"/>
                        <TextBlock x:Name="TxtFooterUpdateStatus" Text="" FontFamily="Segoe UI" FontSize="10" Foreground="{DynamicResource accentBrush}" VerticalAlignment="Center" Margin="6,0,0,0"/>
                        <TextBlock x:Name="TxtFooterError" Text="" FontFamily="Segoe UI" FontSize="10.5" Foreground="{DynamicResource errorBrush}" VerticalAlignment="Center" Margin="10,0,0,0"/>
                    </StackPanel>

                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center" HorizontalAlignment="Right">
                        <Button x:Name="BtnUpdateAll" Content="Tout Mettre à Jour" Height="34" Width="130" Margin="0,0,10,0" Click="BtnUpdateAll_Click"/>
                        <Button x:Name="BtnRefresh" Content="Actualiser" Height="34" Width="100" Margin="0,0,10,0" Click="BtnRefresh_Click"/>
                        <Button x:Name="BtnInstall" Content="Obtenir votre sélection" Height="40" Width="200" Click="BtnInstall_Click">
                            <Button.Style>
                                <Style TargetType="{x:Type Button}" BasedOn="{StaticResource {x:Type Button}}">
                                    <Setter Property="Background" Value="{DynamicResource accentBrush}"/>
                                    <Setter Property="Foreground" Value="{DynamicResource accent_fgBrush}"/>
                                    <Style.Triggers>
                                        <Trigger Property="IsMouseOver" Value="True">
                                            <Setter Property="Opacity" Value="0.9"/>
                                        </Trigger>
                                    </Style.Triggers>
                                </Style>
                            </Button.Style>
                        </Button>
                    </StackPanel>
                </Grid>
            </Border>
        </Grid>
    </Grid>
</Window>