💡 LED Chaser Animation

// LED Chaser Animation — Volt X
// Pins 2-9 connected to 8 LEDs via 220Ω resistors

const int firstPin = 2;   // First LED pin
const int lastPin = 9;    // Last LED pin
int delayTime = 80;       // Speed in ms (lower = faster)

void setup() {
  for (int pin = firstPin; pin <= lastPin; pin++) {
    pinMode(pin, OUTPUT);
  }
}

void loop() {
  // Sweep forward: left to right
  for (int pin = firstPin; pin <= lastPin; pin++) {
    digitalWrite(pin, HIGH);
    delay(delayTime);
    digitalWrite(pin, LOW);
  }
  // Sweep backward: right to left
  for (int pin = lastPin; pin >= firstPin; pin--) {
    digitalWrite(pin, HIGH);
    delay(delayTime);
    digitalWrite(pin, LOW);
  }
}