const int solenoidPin = D0;   // Connected to the MOSFET gate
const int buttonPin = D1;     // Connected to button input

void setup() {
  pinMode(solenoidPin, OUTPUT);
  pinMode(buttonPin, INPUT);  // External pulldown handles logic level

  digitalWrite(solenoidPin, LOW);  // Start solenoid OFF
}

void loop() {
  int buttonState = digitalRead(buttonPin);

  if (buttonState == HIGH) {
    digitalWrite(solenoidPin, HIGH);  // Button pressed → solenoid ON
  } else {
    digitalWrite(solenoidPin, LOW);   // Button released → solenoid OFF
  }
}