bool changeState = false;
bool lastLedState = false;
bool lastButtonD3;
bool lastButtonD4;

void setup() {
  pinMode(D2, OUTPUT);
  pinMode(D3, INPUT);
  pinMode(D4, INPUT);
  Serial.begin(115200);

  digitalWrite(D2, LOW);
  Serial.println("System started. LED is OFF");

  lastButtonD3 = digitalRead(D3) == LOW;
  lastButtonD4 = digitalRead(D4) == LOW;
}

void loop() {
  bool buttonD3 = digitalRead(D3) == LOW;
  bool buttonD4 = digitalRead(D4) == LOW;

  if (buttonD3 && !lastButtonD3) {
    Serial.println("Button D3 pressed");
    changeState = !changeState;
  }
  if (buttonD4 && !lastButtonD4) {
    Serial.println("Button D4 pressed");
    changeState = !changeState;
  }

  lastButtonD3 = buttonD3;
  lastButtonD4 = buttonD4;

  if (changeState) {
    digitalWrite(D2, HIGH);
  } else {
    digitalWrite(D2, LOW);
  }

  if (changeState != lastLedState) {
    if (changeState) {
      Serial.println("LED turned ON");
    } else {
      Serial.println("LED turned OFF");
    }
    lastLedState = changeState;
  }

  delay(20);
}