#include <Adafruit_NeoPixel.h>
#define PIN 6
#define N_LEDS 2
Adafruit_NeoPixel strip = Adafruit_NeoPixel(N_LEDS, PIN, NEO_RGB);
uint32_t red = strip.Color(255, 0, 0); // Red
uint32_t green = strip.Color(0, 255, 0); // Green
uint32_t blue = strip.Color(0, 0, 255); // Blue
uint32_t purple = strip.Color(255, 0, 255); // Purple
uint32_t lightBlue = strip.Color(0, 255, 255); // Light blue
uint32_t yellow = strip.Color(255, 255, 0); // Yellow
uint32_t white = strip.Color(255, 255, 255); // White
void setup() {
  Serial.begin(9600);
  strip.begin();
  strip.show(); // Initialize all pixels to 'off'
  strip.setBrightness(255); //30-255
}
void loop() {
  chase(red); // Red
  chase(green); // Green
  chase(blue); // Blue
  chase(purple); // Purple
  chase(lightBlue); // Light blue
  chase(yellow); // Yellow
  chase(white); // White
}
static void chase(uint32_t c) {
  for (uint16_t i = 0; i < strip.numPixels() + 1; i++) {
    strip.setPixelColor(i  , c); // Draw new pixel
    strip.setPixelColor(i - 1, 0); // Erase pixel a few steps back
    strip.show();
    delay(100);
  }
}