Dark Mode

DARK/LIGHT MODE:

• 3-way picker (system/light/dark) is the standard pattern: @AppStorage("appearance") private var appearance: String = "system" private var preferredColorScheme: ColorScheme? { switch appearance { case "light": return .light; case "dark": return .dark; default: return nil } } .preferredColorScheme(preferredColorScheme) // on outermost container in @main app
• CRITICAL: .preferredColorScheme() MUST be in the root @main app, NOT just in the settings view.
• System option: .preferredColorScheme(nil) follows device setting.
• Settings screen: Picker with light/dark/system options writing to @AppStorage("appearance").

ADAPTIVE THEME COLORS (no color assets needed):

• Switch ALL AppTheme palette colors from plain Color(hex:) to Color(light:dark:) with TWO hex values: static let background = Color(light: Color(hex: "#F8F9FA"), dark: Color(hex: "#1C1C1E")) static let surface = Color(light: Color(hex: "#FFFFFF"), dark: Color(hex: "#2C2C2E"))
• Color(light:dark:) uses UIColor(dynamicProvider:) on iOS/tvOS, NSColor(name:dynamicProvider:) on macOS — reacts to .preferredColorScheme() automatically.
• On macOS, use #if canImport(AppKit) with NSColor instead of UIColor (see design-system skill for full extension).
• YOU decide the dark palette based on app mood — user does not specify dark colors.
• Dark palette guidelines: darken backgrounds (#1C1C1E, #2C2C2E), lighten/brighten accents slightly, use Color.primary/Color.secondary for text.
• AppTheme MUST include the Color(light:dark:) extension (see shared constraints).

PLATFORM RESTRICTIONS:

• visionOS: Dark mode is NOT supported. visionOS glass material auto-adapts to the physical environment. Do not use dark-mode rule_key for visionOS apps.
• macOS: Use NSColor (AppKit), not UIColor (UIKit). See design-system skill for the macOS-specific Color(light:dark:) extension.
• Multi-platform: Use #if canImport(UIKit) / #if canImport(AppKit) guards for the Color(light:dark:) extension in shared code.