themeDark method
Implementation
void themeDark({ThemeData? data, Color? seed, bool? useMaterial3}) {
themeMode = ThemeMode.dark;
if (data != null) {
themeDataDark = data;
} else if (seed != null) {
ColorScheme cs = ColorScheme.fromSeed(seedColor: seed, dynamicSchemeVariant: DynamicSchemeVariant.fidelity, brightness: Brightness.dark);
themeDataDark = ThemeData.from(colorScheme: cs, useMaterial3: useMaterial3);
} else if (useMaterial3 != null) {
themeDataDark = ThemeData.dark(useMaterial3: useMaterial3);
}
}