MainWindow.xaml

<Window x:Class="CLAVEM.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="CLAVEM - File Encryption by Massimo Parisi (antaresfil)"
        Height="630" Width="920"
        MinHeight="570" MinWidth="820"
        WindowStartupLocation="CenterScreen"
        Background="#F5F0E8"
        TextOptions.TextRenderingMode="ClearType"
        TextOptions.TextFormattingMode="Display"
        RenderOptions.ClearTypeHint="Enabled">

    <Window.Resources>

        <!-- Base Button template con ClearType -->
        <Style TargetType="Button">
            <Setter Property="Cursor" Value="Hand"/>
            <Setter Property="FontFamily" Value="Segoe UI"/>
            <Setter Property="BorderThickness" Value="0"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border x:Name="border"
                                Background="{TemplateBinding Background}"
                                BorderBrush="{TemplateBinding BorderBrush}"
                                BorderThickness="{TemplateBinding BorderThickness}"
                                CornerRadius="6"
                                Padding="{TemplateBinding Padding}">
                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"
                                              TextOptions.TextRenderingMode="ClearType"
                                              TextOptions.TextFormattingMode="Display"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsEnabled" Value="False">
                                <Setter TargetName="border" Property="Opacity" Value="0.4"/>
                                <Setter Property="Cursor" Value="Arrow"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>

        <Style TargetType="TextBox">
            <Setter Property="Padding" Value="8,7"/>
            <Setter Property="FontSize" Value="13"/>
            <Setter Property="Background" Value="#FAF7F0"/>
            <Setter Property="BorderBrush" Value="#DDD3B0"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="Foreground" Value="#8B7355"/>
            <Setter Property="VerticalContentAlignment" Value="Center"/>
        </Style>

        <Style TargetType="PasswordBox">
            <Setter Property="Padding" Value="8,7"/>
            <Setter Property="FontSize" Value="13"/>
            <Setter Property="Background" Value="#FAF7F0"/>
            <Setter Property="BorderBrush" Value="#DDD3B0"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="Foreground" Value="#6B5A2E"/>
            <Setter Property="VerticalContentAlignment" Value="Center"/>
        </Style>

        <Style TargetType="CheckBox">
            <Setter Property="FontSize" Value="13"/>
            <Setter Property="Foreground" Value="#8B7355"/>
            <Setter Property="Cursor" Value="Hand"/>
            <Setter Property="VerticalContentAlignment" Value="Center"/>
        </Style>

        <!-- Nav buttons: About / Help con glow hover -->
        <Style x:Key="NavButtonStyle" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
            <Setter Property="Background" Value="#2D1F0A"/>
            <Setter Property="Foreground" Value="#C9A84C"/>
            <Setter Property="BorderBrush" Value="#3D2F10"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="FontSize" Value="12"/>
            <Setter Property="FontWeight" Value="Bold"/>
            <Setter Property="Height" Value="30"/>
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="Background" Value="#3D2F10"/>
                    <Setter Property="Foreground" Value="#FFD966"/>
                    <Setter Property="Effect">
                        <Setter.Value>
                            <DropShadowEffect Color="#FFD040" BlurRadius="12" ShadowDepth="0" Opacity="0.8"/>
                        </Setter.Value>
                    </Setter>
                </Trigger>
            </Style.Triggers>
        </Style>

        <!-- Bottoni outline piccoli footer -->
        <Style x:Key="SmallOutlineButtonStyle" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
            <Setter Property="Background" Value="Transparent"/>
            <Setter Property="Foreground" Value="#A08040"/>
            <Setter Property="BorderBrush" Value="#D4C4A0"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="FontSize" Value="11"/>
            <Setter Property="FontWeight" Value="Bold"/>
            <Setter Property="Height" Value="32"/>
            <Setter Property="Padding" Value="14,0"/>
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="Background" Value="#FDF5E0"/>
                    <Setter Property="BorderBrush" Value="#C9A84C"/>
                    <Setter Property="Foreground" Value="#C9A84C"/>
                </Trigger>
            </Style.Triggers>
        </Style>

        <!-- Browse button scuro -->
        <Style x:Key="BrowseButtonStyle" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
            <Setter Property="Background" Value="#1A1208"/>
            <Setter Property="Foreground" Value="#C9A84C"/>
            <Setter Property="FontSize" Value="12"/>
            <Setter Property="FontWeight" Value="Bold"/>
            <Setter Property="Width" Value="76"/>
            <Setter Property="Height" Value="32"/>
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="Background" Value="#2D1F0A"/>
                    <Setter Property="Foreground" Value="#FFD966"/>
                </Trigger>
            </Style.Triggers>
        </Style>

        <!-- Bottone principale: oro brillante con hover acceso e click -->
        <Style x:Key="ExecuteButtonStyle" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
            <Setter Property="FontFamily" Value="Palatino Linotype"/>
            <Setter Property="FontSize" Value="15"/>
            <Setter Property="FontWeight" Value="Bold"/>
            <Setter Property="Foreground" Value="White"/>
            <Setter Property="Height" Value="42"/>
            <Setter Property="Padding" Value="36,0"/>
            <Setter Property="BorderThickness" Value="0"/>
            <Setter Property="Background">
                <Setter.Value>
                    <LinearGradientBrush StartPoint="0,0" EndPoint="1,1">
                        <GradientStop Color="#D4A830" Offset="0"/>
                        <GradientStop Color="#A07010" Offset="1"/>
                    </LinearGradientBrush>
                </Setter.Value>
            </Setter>
            <Setter Property="Effect">
                <Setter.Value>
                    <DropShadowEffect Color="#A07010" BlurRadius="10" ShadowDepth="2" Opacity="0.45"/>
                </Setter.Value>
            </Setter>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border x:Name="border"
                                Background="{TemplateBinding Background}"
                                CornerRadius="8"
                                Padding="{TemplateBinding Padding}">
                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"
                                              TextOptions.TextRenderingMode="ClearType"
                                              TextOptions.TextFormattingMode="Display"/>
                        </Border>
                        <ControlTemplate.Triggers>
                            <!-- Hover: oro vivo luminoso -->
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="border" Property="Background">
                                    <Setter.Value>
                                        <LinearGradientBrush StartPoint="0,0" EndPoint="1,1">
                                            <GradientStop Color="#FFD966" Offset="0"/>
                                            <GradientStop Color="#C88A10" Offset="1"/>
                                        </LinearGradientBrush>
                                    </Setter.Value>
                                </Setter>
                                <Setter Property="Effect">
                                    <Setter.Value>
                                        <DropShadowEffect Color="#FFD040" BlurRadius="20" ShadowDepth="0" Opacity="0.8"/>
                                    </Setter.Value>
                                </Setter>
                            </Trigger>
                            <!-- Click: più scuro -->
                            <Trigger Property="IsPressed" Value="True">
                                <Setter TargetName="border" Property="Background">
                                    <Setter.Value>
                                        <LinearGradientBrush StartPoint="0,0" EndPoint="1,1">
                                            <GradientStop Color="#B8860B" Offset="0"/>
                                            <GradientStop Color="#8B6400" Offset="1"/>
                                        </LinearGradientBrush>
                                    </Setter.Value>
                                </Setter>
                                <Setter TargetName="border" Property="Opacity" Value="0.9"/>
                            </Trigger>
                            <Trigger Property="IsEnabled" Value="False">
                                <Setter TargetName="border" Property="Opacity" Value="0.35"/>
                                <Setter Property="Cursor" Value="Arrow"/>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>

    </Window.Resources>

    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>

        <!-- ══════════════ HEADER ══════════════ -->
        <Border Grid.Row="0" Background="#1A1208" Padding="22,14"
                TextOptions.TextRenderingMode="ClearType"
                TextOptions.TextFormattingMode="Display">
            <Border.Effect>
                <DropShadowEffect Color="#000000" BlurRadius="14" ShadowDepth="2" Opacity="0.5"/>
            </Border.Effect>
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="*"/>
                    <ColumnDefinition Width="Auto"/>
                </Grid.ColumnDefinitions>

                <StackPanel Grid.Column="0" Orientation="Horizontal" VerticalAlignment="Center">
                    <Border CornerRadius="12" Width="68" Height="68" Margin="0,0,16,0" ClipToBounds="True">
                        <Border.Effect>
                            <DropShadowEffect Color="#000000" BlurRadius="12" ShadowDepth="2" Opacity="0.5"/>
                        </Border.Effect>
                        <Image Source="Resources/clavem_logo.png" Width="68" Height="68"
                               RenderOptions.BitmapScalingMode="HighQuality"
                               Stretch="UniformToFill"/>
                    </Border>
                    <StackPanel VerticalAlignment="Center">
                        <TextBlock Text="CLAVEM"
                                   FontFamily="Palatino Linotype"
                                   FontSize="22" FontWeight="Bold"
                                   Foreground="#E8C040"/>
                        <TextBlock Text="FILE ENCRYPTION  ·  ANTARESFIL"
                                   FontFamily="Segoe UI" FontSize="10" FontWeight="SemiBold"
                                   Foreground="#C4A44A" Margin="1,3,0,0"/>
                    </StackPanel>
                </StackPanel>

                <StackPanel Grid.Column="1" Orientation="Horizontal" VerticalAlignment="Center">
                    <!-- Status pill verde pulsante -->
                    <Border CornerRadius="12" Padding="10,4" Margin="0,0,14,0"
                            Background="#0A2A14" BorderBrush="#1A5530" BorderThickness="1">
                        <StackPanel Orientation="Horizontal" VerticalAlignment="Center">
                            <Ellipse Width="7" Height="7" Fill="#22C55E" Margin="0,0,6,0">
                                <Ellipse.Effect>
                                    <DropShadowEffect Color="#22C55E" BlurRadius="8" ShadowDepth="0" Opacity="1"/>
                                </Ellipse.Effect>
                            </Ellipse>
                            <TextBlock x:Name="StatusText" Text="READY"
                                       FontFamily="Segoe UI" FontSize="10" FontWeight="Bold"
                                       Foreground="#22C55E"/>
                        </StackPanel>
                    </Border>

                    <Button Content="ℹ  About" Click="AboutButton_Click"
                            Width="80" Margin="0,0,6,0" Padding="8,0"
                            Style="{StaticResource NavButtonStyle}"/>
                    <Button Content="📚  Help IT" Click="HelpIT_Click"
                            Width="88" Margin="0,0,6,0" Padding="8,0"
                            Style="{StaticResource NavButtonStyle}"/>
                    <Button Content="📚  Help EN" Click="HelpEN_Click"
                            Width="88" Padding="8,0"
                            Style="{StaticResource NavButtonStyle}"/>
                </StackPanel>
            </Grid>
        </Border>

        <!-- ══════════════ TABS ══════════════ -->
        <Border Grid.Row="1" Background="#211608" BorderBrush="#3D2F10" BorderThickness="0,0,0,1">
            <StackPanel Orientation="Horizontal">

                <!-- Encrypt tab: oro brillante se attivo, oro medio se inattivo -->
                <RadioButton x:Name="EncryptRadioButton"
                             Content="🔒  Encrypt File"
                             GroupName="Operation" IsChecked="True"
                             Checked="OperationMode_Changed"
                             FontFamily="Palatino Linotype"
                             FontSize="14" FontWeight="Bold"
                             Padding="28,13" Margin="0" Cursor="Hand">
                    <RadioButton.Template>
                        <ControlTemplate TargetType="RadioButton">
                            <Border x:Name="tb" Background="Transparent"
                                    BorderThickness="0,0,0,2" BorderBrush="Transparent"
                                    Padding="{TemplateBinding Padding}" Cursor="Hand">
                                <TextBlock x:Name="label" Text="🔒  Encrypt File"
                                           FontFamily="Palatino Linotype" FontSize="14" FontWeight="Bold"
                                           Foreground="#9A7A30"
                                           TextOptions.TextRenderingMode="ClearType"
                                           TextOptions.TextFormattingMode="Display"/>
                            </Border>
                            <ControlTemplate.Triggers>
                                <Trigger Property="IsChecked" Value="True">
                                    <Setter TargetName="tb" Property="BorderBrush" Value="#E8C040"/>
                                    <Setter TargetName="tb" Property="Background" Value="#1A0F04"/>
                                    <Setter TargetName="label" Property="Foreground" Value="#E8C040"/>
                                </Trigger>
                                <Trigger Property="IsMouseOver" Value="True">
                                    <Setter TargetName="tb" Property="Background" Value="#160C03"/>
                                    <Setter TargetName="label" Property="Foreground" Value="#C9A84C"/>
                                </Trigger>
                            </ControlTemplate.Triggers>
                        </ControlTemplate>
                    </RadioButton.Template>
                </RadioButton>

                <!-- Decrypt tab: oro medio se attivo, grigio-oro se inattivo -->
                <RadioButton x:Name="DecryptRadioButton"
                             Content="🔓  Decrypt File"
                             GroupName="Operation"
                             Checked="OperationMode_Changed"
                             FontFamily="Palatino Linotype"
                             FontSize="14" FontWeight="Bold"
                             Padding="28,13" Margin="0" Cursor="Hand">
                    <RadioButton.Template>
                        <ControlTemplate TargetType="RadioButton">
                            <Border x:Name="tb" Background="Transparent"
                                    BorderThickness="0,0,0,2" BorderBrush="Transparent"
                                    Padding="{TemplateBinding Padding}" Cursor="Hand">
                                <TextBlock x:Name="label" Text="🔓  Decrypt File"
                                           FontFamily="Palatino Linotype" FontSize="14" FontWeight="Bold"
                                           Foreground="#6A5828"
                                           TextOptions.TextRenderingMode="ClearType"
                                           TextOptions.TextFormattingMode="Display"/>
                            </Border>
                            <ControlTemplate.Triggers>
                                <Trigger Property="IsChecked" Value="True">
                                    <Setter TargetName="tb" Property="BorderBrush" Value="#E8C040"/>
                                    <Setter TargetName="tb" Property="Background" Value="#1A0F04"/>
                                    <Setter TargetName="label" Property="Foreground" Value="#E8C040"/>
                                </Trigger>
                                <Trigger Property="IsMouseOver" Value="True">
                                    <Setter TargetName="tb" Property="Background" Value="#160C03"/>
                                    <Setter TargetName="label" Property="Foreground" Value="#C9A84C"/>
                                </Trigger>
                            </ControlTemplate.Triggers>
                        </ControlTemplate>
                    </RadioButton.Template>
                </RadioButton>

            </StackPanel>
        </Border>

        <!-- ══════════════ BODY ══════════════ -->
        <Grid Grid.Row="2" Background="#F5F0E8" Margin="18,16,18,0">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*"/>
                <ColumnDefinition Width="16"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>

            <!-- Pannello SINISTRA: File Selection -->
            <Border Grid.Column="0" Background="White" CornerRadius="10"
                    BorderBrush="#E8DFC8" BorderThickness="1">
                <Border.Effect>
                    <DropShadowEffect Color="#1A1208" BlurRadius="8" ShadowDepth="1" Opacity="0.07"/>
                </Border.Effect>
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="*"/>
                    </Grid.RowDefinitions>
                    <Border Grid.Row="0" CornerRadius="10,10,0,0"
                            Padding="14,9" BorderBrush="#E0D4B0" BorderThickness="0,0,0,1">
                        <Border.Background>
                            <LinearGradientBrush StartPoint="0,0" EndPoint="1,0">
                                <GradientStop Color="#F5EED8" Offset="0"/>
                                <GradientStop Color="#EDE5CC" Offset="1"/>
                            </LinearGradientBrush>
                        </Border.Background>
                        <TextBlock Text="FILE SELECTION"
                                   FontFamily="Palatino Linotype"
                                   FontSize="10" FontWeight="Bold"
                                   Foreground="#8B6914"
                                   TextOptions.TextRenderingMode="ClearType"
                                   TextOptions.TextFormattingMode="Display"/>
                    </Border>
                    <StackPanel Grid.Row="1" Margin="16,14,16,16">

                        <Grid Margin="0,0,0,10">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="60"/>
                                <ColumnDefinition Width="*"/>
                                <ColumnDefinition Width="Auto"/>
                            </Grid.ColumnDefinitions>
                            <TextBlock Grid.Column="0" Text="FILE"
                                       FontFamily="Segoe UI" FontSize="11" FontWeight="Bold"
                                       Foreground="#A08040" VerticalAlignment="Center"
                                       TextOptions.TextRenderingMode="ClearType"
                                       TextOptions.TextFormattingMode="Display"/>
                            <TextBox x:Name="FilePathTextBox" Grid.Column="1"
                                     IsReadOnly="True" Margin="0,0,8,0"
                                     TextChanged="FilePathTextBox_TextChanged"/>
                            <Button x:Name="BrowseButton" Grid.Column="2"
                                    Content="Browse..." Click="BrowseButton_Click"
                                    Style="{StaticResource BrowseButtonStyle}"/>
                        </Grid>

                        <Border x:Name="FileInfoPanel" Visibility="Collapsed"
                                Background="#FDF8EC" BorderBrush="#E0D4B0"
                                BorderThickness="1" CornerRadius="6"
                                Padding="10,8" Margin="0,0,0,10">
                            <StackPanel>
                                <TextBlock x:Name="FileInfoText" FontWeight="Bold"
                                           Foreground="#6B5A2E" FontSize="13"
                                           TextOptions.TextRenderingMode="ClearType"/>
                                <TextBlock x:Name="FileInfoDetails" Foreground="#A08040"
                                           FontSize="12" Margin="0,3,0,0" TextWrapping="Wrap"
                                           TextOptions.TextRenderingMode="ClearType"/>
                                <TextBlock x:Name="EncryptedFileWarning"
                                           Visibility="Collapsed"
                                           Text="⛔  This file is already encrypted (.svlt). Select a different file."
                                           Foreground="#C0392B" FontSize="12" FontWeight="Bold"
                                           Margin="0,3,0,0" TextWrapping="Wrap"
                                           TextOptions.TextRenderingMode="ClearType"/>
                            </StackPanel>
                        </Border>

                        <Grid Margin="0,0,0,12">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="60"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <TextBlock Grid.Column="0" Text="OUTPUT"
                                       FontFamily="Segoe UI" FontSize="11" FontWeight="Bold"
                                       Foreground="#A08040" VerticalAlignment="Center"
                                       TextOptions.TextRenderingMode="ClearType"
                                       TextOptions.TextFormattingMode="Display"/>
                            <TextBox x:Name="OutputPathTextBox" Grid.Column="1" IsReadOnly="True"/>
                        </Grid>

                        <Separator Background="#E8DFC8" Margin="0,0,0,12"/>

                        <CheckBox x:Name="SecureDeleteCheckBox" IsChecked="True"
                                  Content="Secure delete original file after encryption (3-pass)"/>
                    </StackPanel>
                </Grid>
            </Border>

            <!-- Pannello DESTRA: Authentication -->
            <Border Grid.Column="2" Background="White" CornerRadius="10"
                    BorderBrush="#E8DFC8" BorderThickness="1">
                <Border.Effect>
                    <DropShadowEffect Color="#1A1208" BlurRadius="8" ShadowDepth="1" Opacity="0.07"/>
                </Border.Effect>
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="*"/>
                    </Grid.RowDefinitions>
                    <Border Grid.Row="0" CornerRadius="10,10,0,0"
                            Padding="14,9" BorderBrush="#E0D4B0" BorderThickness="0,0,0,1">
                        <Border.Background>
                            <LinearGradientBrush StartPoint="0,0" EndPoint="1,0">
                                <GradientStop Color="#F5EED8" Offset="0"/>
                                <GradientStop Color="#EDE5CC" Offset="1"/>
                            </LinearGradientBrush>
                        </Border.Background>
                        <TextBlock Text="AUTHENTICATION"
                                   FontFamily="Palatino Linotype"
                                   FontSize="10" FontWeight="Bold"
                                   Foreground="#8B6914"
                                   TextOptions.TextRenderingMode="ClearType"
                                   TextOptions.TextFormattingMode="Display"/>
                    </Border>
                    <StackPanel Grid.Row="1" Margin="16,14,16,16">

                        <Grid Margin="0,0,0,10">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="76"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <TextBlock Grid.Column="0" Text="PASSWORD"
                                       FontFamily="Segoe UI" FontSize="11" FontWeight="Bold"
                                       Foreground="#A08040" VerticalAlignment="Center"
                                       TextOptions.TextRenderingMode="ClearType"
                                       TextOptions.TextFormattingMode="Display"/>
                            <PasswordBox x:Name="PasswordBox" Grid.Column="1"
                                         PasswordChanged="PasswordBox_PasswordChanged"/>
                        </Grid>

                        <StackPanel x:Name="ConfirmPasswordPanel" Margin="0,0,0,10">
                            <Grid>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="76"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <TextBlock Grid.Column="0" Text="CONFIRM"
                                           FontFamily="Segoe UI" FontSize="11" FontWeight="Bold"
                                           Foreground="#A08040" VerticalAlignment="Center"
                                           TextOptions.TextRenderingMode="ClearType"
                                           TextOptions.TextFormattingMode="Display"/>
                                <PasswordBox x:Name="ConfirmPasswordBox" Grid.Column="1"
                                             PasswordChanged="AuthFactor_Changed"/>
                            </Grid>
                            <TextBlock x:Name="PasswordMismatchText"
                                       Text="Passwords do not match."
                                       Foreground="#C0392B" FontSize="12"
                                       Margin="76,4,0,0" Visibility="Collapsed"
                                       TextOptions.TextRenderingMode="ClearType"/>
                        </StackPanel>

                        <Separator Background="#E8DFC8" Margin="0,2,0,12"/>

                        <CheckBox x:Name="UseKeyFileCheckBox"
                                  Content="Use Keyfile (cryptographic second factor)"
                                  Checked="AuthFactor_Changed" Unchecked="AuthFactor_Changed"
                                  Margin="0,0,0,10"/>

                        <Grid>
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="76"/>
                                <ColumnDefinition Width="*"/>
                                <ColumnDefinition Width="Auto"/>
                            </Grid.ColumnDefinitions>
                            <TextBlock Grid.Column="0" Text="KEYFILE"
                                       FontFamily="Segoe UI" FontSize="11" FontWeight="Bold"
                                       Foreground="#A08040" VerticalAlignment="Center"
                                       TextOptions.TextRenderingMode="ClearType"
                                       TextOptions.TextFormattingMode="Display"/>
                            <TextBox x:Name="KeyFilePathTextBox" Grid.Column="1"
                                     IsReadOnly="True" Margin="0,0,8,0"
                                     TextChanged="AuthFactor_Changed"/>
                            <Button x:Name="BrowseKeyFileButton" Grid.Column="2"
                                    Content="Browse..." Click="BrowseKeyFileButton_Click"
                                    Style="{StaticResource BrowseButtonStyle}"/>
                        </Grid>

                    </StackPanel>
                </Grid>
            </Border>
        </Grid>

        <!-- ══════════════ FOOTER ══════════════ -->
        <Border Grid.Row="3" Background="White"
                BorderBrush="#E8DFC8" BorderThickness="0,1,0,0"
                Padding="18,12" Margin="0,14,0,0">
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="*"/>
                    <ColumnDefinition Width="Auto"/>
                </Grid.ColumnDefinitions>

                <StackPanel Grid.Column="0" Orientation="Horizontal" VerticalAlignment="Center">
                    <Button x:Name="SetupGuideButton"
                            Content="📖  Setup Guide"
                            Click="SetupGuideButton_Click"
                            Margin="0,0,8,0"
                            Style="{StaticResource SmallOutlineButtonStyle}"/>
                    <Button x:Name="VerifyIntegrityButton"
                            Content="🔎  Verify Integrity"
                            Click="VerifyIntegrityButton_Click"
                            Style="{StaticResource SmallOutlineButtonStyle}"/>
                </StackPanel>

                <Button x:Name="ExecuteButton" Grid.Column="1"
                        Content="Encrypt File"
                        Click="ExecuteButton_Click"
                        IsEnabled="False"
                        Style="{StaticResource ExecuteButtonStyle}"/>
            </Grid>
        </Border>

        <!-- ══════════════ PROGRESS ══════════════ -->
        <Border Grid.Row="4" x:Name="ProgressPanel" Visibility="Collapsed"
                Background="#FDF8EC" BorderBrush="#E0D4B0"
                BorderThickness="0,1,0,0" Padding="18,12">
            <StackPanel>
                <TextBlock x:Name="ProgressText" Text="Processing..."
                           FontFamily="Segoe UI" FontSize="13" FontWeight="Bold"
                           Foreground="#6B5A2E" Margin="0,0,0,8"
                           TextOptions.TextRenderingMode="ClearType"
                           TextOptions.TextFormattingMode="Display"/>
                <ProgressBar x:Name="ProgressBar" Height="5" IsIndeterminate="True">
                    <ProgressBar.Foreground>
                        <LinearGradientBrush StartPoint="0,0" EndPoint="1,0">
                            <GradientStop Color="#E8C040" Offset="0"/>
                            <GradientStop Color="#FFD966" Offset="1"/>
                        </LinearGradientBrush>
                    </ProgressBar.Foreground>
                </ProgressBar>
            </StackPanel>
        </Border>

    </Grid>
</Window>