#include <Adafruit_NeoPixel.h>

#define PIN        7
#define NUM_LEDS  16

Adafruit_NeoPixel strip(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800);

int potPin = A0;
int potValue = 0;

void setup() {
  strip.begin();
  strip.show(); // Initialize all pixels to 'off'
}

void loop() {
  potValue = analogRead(potPin);

  int ledOffset = map(potValue, 0, 1023, 0, NUM_LEDS);

  for (int i = 0; i < NUM_LEDS; i++) {
    int pixelIndex = (i + ledOffset) % NUM_LEDS;
    strip.setPixelColor(i, 0, 0, 0);
    strip.setPixelColor(pixelIndex, 255, 255, 255);
  }
  strip.show();
  delay(10);
}