SchemeRainbow constructor 
    
      
      SchemeRainbow({ - required Hct sourceColorHct, 
- required bool isDark, 
- required double contrastLevel, 
})Implementation
  SchemeRainbow({
  required Hct sourceColorHct,
  required super.isDark,
  required super.contrastLevel,
}) : super(
        sourceColorArgb: sourceColorHct.toInt(),
        variant: Variant.rainbow,
        primaryPalette: TonalPalette.of(
          sourceColorHct.hue,
          48.0,
        ),
        secondaryPalette: TonalPalette.of(
          sourceColorHct.hue,
          16.0,
        ),
        tertiaryPalette: TonalPalette.of(
          MathUtils.sanitizeDegreesDouble(sourceColorHct.hue + 60.0),
          24.0,
        ),
        neutralPalette: TonalPalette.of(
          sourceColorHct.hue,
          0.0,
        ),
        neutralVariantPalette: TonalPalette.of(
          sourceColorHct.hue,
          0.0,
        ),
      );