gregExtractor/GUI/MainWindow.axaml

<Window xmlns="https://github.com/avaloniaui"
        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:vm="clr-namespace:gregExtractor.GUI.ViewModels"
        xmlns:views="clr-namespace:gregExtractor.GUI.Views"
        mc:Ignorable="d"
        x:Class="gregExtractor.GUI.MainWindow"
        Width="1540"
        Height="940"
        MinWidth="1280"
        MinHeight="820"
        Title="gregExtractor">
  <Window.DataTemplates>
    <DataTemplate DataType="vm:ExtractorViewModel">
      <views:ExtractorView />
    </DataTemplate>
    <DataTemplate DataType="vm:CoverageViewModel">
      <views:CoverageView />
    </DataTemplate>
    <DataTemplate DataType="vm:SyncViewModel">
      <views:SyncView />
    </DataTemplate>
    <DataTemplate DataType="vm:CreateViewModel">
      <views:CreateView />
    </DataTemplate>
    <DataTemplate DataType="vm:HookBrowserViewModel">
      <views:HookBrowserView />
    </DataTemplate>
    <DataTemplate DataType="vm:SettingsViewModel">
      <views:SettingsView />
    </DataTemplate>
  </Window.DataTemplates>

  <Grid RowDefinitions="Auto,*" Margin="12">
    <Border Grid.Row="0" Classes="greg-card" Padding="8" Margin="0,0,0,12">
      <Grid ColumnDefinitions="Auto,*,Auto,Auto,Auto">
        <TextBlock Text="gregExtractor" FontSize="18" FontWeight="SemiBold" VerticalAlignment="Center"/>
        <StackPanel Grid.Column="1" Orientation="Horizontal" Spacing="8" VerticalAlignment="Center">
          <Border Classes="badge-covered">
            <TextBlock Text="Game" FontSize="11"/>
          </Border>
          <TextBlock Text="{Binding GamePathHint}" Classes="greg-secondary"/>
        </StackPanel>
        <TextBlock Grid.Column="2" Text="{Binding VersionText}" VerticalAlignment="Center" Classes="greg-secondary"/>
        <Button Grid.Column="3" Content="🗕" Classes="greg-secondary" Click="OnMinimizeClicked" Width="36"/>
        <Button Grid.Column="4" Content="✕" Classes="greg-danger" Click="OnCloseClicked" Width="36"/>
      </Grid>
    </Border>

    <Grid Grid.Row="1" ColumnDefinitions="250,*">
      <Border Grid.Column="0" Classes="greg-card">
        <Grid RowDefinitions="Auto,*,Auto">
          <TextBlock Text="Navigation" FontSize="16" FontWeight="SemiBold"/>
          <ItemsControl Grid.Row="1" ItemsSource="{Binding NavigationItems}">
            <ItemsControl.ItemTemplate>
              <DataTemplate>
                <Button Classes="greg-nav"
                        Margin="0,0,0,6"
                        Command="{Binding DataContext.SelectNavItemCommand, RelativeSource={RelativeSource AncestorType=Window}}"
                        CommandParameter="{Binding}">
                  <Grid ColumnDefinitions="Auto,*">
                    <TextBlock Text="{Binding Icon}"/>
                    <TextBlock Grid.Column="1" Text="{Binding Title}"/>
                  </Grid>
                </Button>
              </DataTemplate>
            </ItemsControl.ItemTemplate>
          </ItemsControl>
          <TextBlock Grid.Row="2" Text="FrikaMF / GregFramework" Classes="greg-secondary" FontSize="11"/>
        </Grid>
      </Border>

      <Border Grid.Column="1" Classes="greg-card" Padding="12">
        <ContentControl Content="{Binding CurrentPageViewModel}"/>
      </Border>
    </Grid>
  </Grid>
</Window>