// Source: https://github.com/s-marley/FastLED-basics

#include <FastLED.h>

#define NUM_LEDS  18
#define LED_PIN   2

CRGB leds[NUM_LEDS];

void setup() {
  FastLED.addLeds<WS2812B, LED_PIN, GRB>(leds, NUM_LEDS);
  FastLED.setBrightness(50);
}

void loop() {

  fill_solid(leds, NUM_LEDS, CRGB::Red);
  FastLED.show();
  delay(500);
  
  fill_solid(leds, NUM_LEDS, CRGB::Green);
  FastLED.show();
  delay(500);
  
  fill_solid(leds, NUM_LEDS, CRGB::Blue);
  FastLED.show();
  delay(500);

  fill_gradient_RGB(leds, NUM_LEDS, CRGB::Magenta, CRGB::Yellow);
  FastLED.show();
  delay(500);

  fill_gradient_RGB(leds, NUM_LEDS, CRGB::Red, CRGB::Yellow, CRGB::Green, CRGB::Blue);
  FastLED.show();
  delay(500);

  fill_rainbow(leds, NUM_LEDS, 0, 255 / NUM_LEDS);
  FastLED.show();
  delay(500);
}