Customizer controls
The customizer lives in AppShell and is available from the topbar.
It controls theme mode, primary color, semi dark menu, and content width.
Primary colors
Primary color options are defined in components/app-shell.tsx.
Changing primary color updates --primary and --primary-strong on the document element and persists the selected color in localStorage.
Content width
Compact content keeps the page width constrained.
Wide content lets page stacks use more horizontal space.