MainWindow.xaml

<Window x:Class="SpawnDev.ILGPU.WpfDemo.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="SpawnDev.ILGPU — Desktop Demo"
        Width="1400" Height="900"
        MinWidth="900" MinHeight="600"
        Background="{StaticResource BgDeepBrush}"
        WindowStartupLocation="CenterScreen">

    <!-- Resources MUST come before content that references them -->
    <Window.Resources>
        <!-- Navigation button style (radio button as nav item) -->
        <Style x:Key="NavButtonStyle" TargetType="RadioButton">
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="RadioButton">
                        <Border x:Name="Bd" Padding="16,10" Margin="6,2" CornerRadius="6"
                                Background="Transparent" Cursor="Hand">
                            <ContentPresenter />
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="Bd" Property="Background" Value="#2A2A4A" />
                            </Trigger>
                            <Trigger Property="IsChecked" Value="True">
                                <Setter TargetName="Bd" Property="Background">
                                    <Setter.Value>
                                        <LinearGradientBrush StartPoint="0,0" EndPoint="1,0">
                                            <GradientStop Color="#2B3B8B" Offset="0" />
                                            <GradientStop Color="#3B2B7B" Offset="1" />
                                        </LinearGradientBrush>
                                    </Setter.Value>
                                </Setter>
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Setter Property="Foreground" Value="{StaticResource TextSecondaryBrush}" />
            <Setter Property="FontSize" Value="13.5" />
            <Setter Property="GroupName" Value="Nav" />
        </Style>

        <!-- Link-style button -->
        <Style x:Key="NavLinkStyle" TargetType="Button">
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Border x:Name="Bd" Padding="16,8" Margin="6,1" CornerRadius="4"
                                Background="Transparent" Cursor="Hand">
                            <ContentPresenter />
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="True">
                                <Setter TargetName="Bd" Property="Background" Value="#2A2A4A" />
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Setter Property="Foreground" Value="{StaticResource TextMutedBrush}" />
            <Setter Property="FontSize" Value="12.5" />
        </Style>
    </Window.Resources>

    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="220" />
            <ColumnDefinition Width="*" />
        </Grid.ColumnDefinitions>

        <!-- Sidebar Navigation -->
        <Border Grid.Column="0" Background="{StaticResource BgMainBrush}"
                BorderBrush="{StaticResource BorderSubtleBrush}" BorderThickness="0,0,1,0">
            <DockPanel>
                <!-- Brand header -->
                <Border DockPanel.Dock="Top" Padding="16,14" 
                        Background="#1E1E3A" BorderBrush="{StaticResource BorderSubtleBrush}" BorderThickness="0,0,0,1">
                    <TextBlock Text="SpawnDev.ILGPU" FontSize="16" FontWeight="Bold"
                               Foreground="{StaticResource TextPrimaryBrush}" />
                </Border>

                <!-- Footer links -->
                <StackPanel DockPanel.Dock="Bottom" Margin="0,0,0,12">
                    <Separator Background="{StaticResource BorderSubtleBrush}" Margin="16,8" />
                    <Button Content="🔗  Project GitHub" Click="OnGitHubClick" Style="{StaticResource NavLinkStyle}" />
                    <Button Content="📖  ILGPU.net" Click="OnIlgpuNetClick" Style="{StaticResource NavLinkStyle}" />
                </StackPanel>

                <!-- Nav items -->
                <StackPanel Margin="0,8,0,0">
                    <RadioButton x:Name="NavHome" Content="🏠  Home"
                                 Style="{StaticResource NavButtonStyle}"
                                 IsChecked="True" Checked="OnNavChanged" Tag="Home" />
                    <RadioButton x:Name="NavFractal" Content="🎨  Fractal Explorer"
                                 Style="{StaticResource NavButtonStyle}"
                                 Checked="OnNavChanged" Tag="Fractal" />
                    <RadioButton x:Name="NavRaymarch" Content="🌐  3D Explorer"
                                 Style="{StaticResource NavButtonStyle}"
                                 Checked="OnNavChanged" Tag="Raymarch" />
                    <RadioButton x:Name="NavBoids" Content="🐦  GPU Boids"
                                 Style="{StaticResource NavButtonStyle}"
                                 Checked="OnNavChanged" Tag="Boids" />
                    <RadioButton x:Name="NavBenchmarks" Content="⚡  Benchmarks"
                                 Style="{StaticResource NavButtonStyle}"
                                 Checked="OnNavChanged" Tag="Benchmarks" />

                </StackPanel>
            </DockPanel>
        </Border>

        <!-- Content area -->
        <ContentControl x:Name="ContentArea" Grid.Column="1" />
    </Grid>
</Window>