/// ========== IGNORE ========== ///
#include "FastLED.h"
#include <SPI.h>
#define NUM_LEDS    100
CRGB leds[NUM_LEDS]; void setup() { FastLED.addLeds<WS2811, 5, GRB>(leds, NUM_LEDS); }
/// ========== IGNORE ========== ///

int hue = 0;

void loop() {
  FastLED.clear();

  for (int i = 0; i < NUM_LEDS; i++) {
    int newHue = (hue + i) % 255;
    leds[i] = CHSV(newHue, 255, 255);
  }

  delay(20);
  hue = (hue + 1) % 255;

  FastLED.show();
}