docs: public static ImageOption backgroundColorOf(int r, int g, int b) {
      if (r > 255 || r < 0) {
        throw new IllegalArgumentException("Red component out of range: " + r);
      }
      if (g > 255 || g < 0) {
        throw new IllegalArgumentException("Green component out of range: " + g);
      }
      if (b > 255 || b < 0) {
        throw new IllegalArgumentException("Blue component out of range: " + b);
      }
  
      return new ImageOption("bg", "rgb:" + format(Locale.getDefault(), "%02X%02X%02X", r, g, b));
    }