#include <Arduino.h>
#include <Adafruit_NeoPixel.h>

// Built-in RGB LED pin (usually GPIO8 on ESP32-C3 Mini)
#define RGB_PIN 8
#define NUMPIXELS 5   // only one built-in LED

Adafruit_NeoPixel pixels(NUMPIXELS, RGB_PIN, NEO_GRB + NEO_KHZ800);

void setup() {
  pixels.begin(); // initialize NeoPixel
  pixels.setBrightness(50); // adjust brightness (0–255)
}

void loop() {
  // Rainbow animation
  for (int i = 0; i < 256; i++) {
    uint32_t color = pixels.Color(
      (sin((i + 0) * 0.024) * 127) + 128,   // Red
      (sin((i + 85) * 0.024) * 127) + 128,  // Green
      (sin((i + 170) * 0.024) * 127) + 128  // Blue
    );
    pixels.setPixelColor(0, color);
    pixels.show();
    delay(20); // adjust speed
  }
}