void setup() {
  pinMode(PB0, OUTPUT);
}

void loop() {
  // Flickering effect
  for (int i = 0; i < 8; i++) {
    analogWrite(PB0, random(10, 200));
    delay(random(30, 100));
  }

  for (int i = 0; i < 5; i++) {
    analogWrite(PB0, random(10, 200));
    delay(random(20, 80));
  }
}