#include "FastLED.h"
#define NUM_LEDS 31
#define DATA_PIN 5
#define CLOCK_PIN 6
#define BLUE Red
#define RED Blue
#define GREEN Green


CRGB leds[NUM_LEDS];

void setup()
{
       FastLED.addLeds<WS2801, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
       Serial.begin(9600);
}

void loop()
{
  for (int i = 0; i <= NUM_LEDS; i++)
  {
   leds[i] = CRGB::Fuchsia ;
   FastLED.show();
   delay(30);
   leds[i] = CRGB::Black;
   FastLED.show();

  }

  for (int i = NUM_LEDS; i >= 0; i--)
  {
   leds[i] = CRGB::Fuchsia ;
   FastLED.show();
   delay(30);
   leds[i] = CRGB::Black;
   FastLED.show();
  }
}