// Pin connected to the onboard LED
const int ledPin = 13;
const int minBrightness = 1; // Minimum brightness level

void setup() {
  // Initialize the onboard LED pin as an output
  pinMode(ledPin, OUTPUT);
}

void loop() {
  // Gradually increase brightness (fade in)
  for (int brightness = minBrightness; brightness <= 255; brightness++) {
    analogWrite(ledPin, brightness);  // Set LED brightness using PWM
    delay(15);  // Small delay for a smooth transition
  }
  
  // Keeping the LED at full brightness for a moment
  delay(500);  // You can adjust the delay duration here

  // Gradually decrease brightness (fade out)
  for (int brightness = 255; brightness >= minBrightness; brightness--) {
    analogWrite(ledPin, brightness);  // Set LED brightness using PWM
    delay(15);  // Small delay for a smooth transition
  }
  
  // Keeping the LED at minimum brightness for a moment
  delay(100);  // You can adjust the delay duration here
}