scheme static method
Implementation
static void scheme({Color? neutral, Color? error, Color? success, Color? warning, Color? message}) {
palette.at(#neutral)[palette.at(#accent)[Colors.blueGrey]] = neutral;
palette.at(#error)[Colors.redAccent] = error;
palette.at(#success)[Colors.green] = success;
palette.at(#warning)[Colors.amber] = warning;
palette.at(#message)[Colors.brown] = message;
}