#include <neopixel.h>

// IMPORTANT: Set pixel COUNT, PIN and TYPE
#define PIXEL_PIN D2
#define PIXEL_COUNT 16
#define PIXEL_TYPE WS2812
 
Adafruit_NeoPixel strip = Adafruit_NeoPixel(PIXEL_COUNT, PIXEL_PIN, PIXEL_TYPE);

void setup() {
    strip.begin();
    
    uint32_t c1 = strip.Color(0, 255, 0);
    uint32_t c2 = strip.Color(0, 0, 0);
    
     int numPixels = strip.numPixels();
    
    for( int i = 0; i < numPixels; i++ ){
        strip.setPixelColor(i, c1); // set a color 
                
        strip.show(); // set updates to the strip
        delay(300); 
    }


    for( int i = numPixels; i >= 0; i-- ) {
        strip.setPixelColor(i, c2); // remove the color

        strip.show();
                
        delay(300);
    }
}