int gasSensor = A0;   // MQ-2 connected to A0
int ledPin = 13;      // LED connected to pin 13
int gasValue = 0;
int threshold = 800; // Adjust based on sensor

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  gasValue = analogRead(gasSensor);
  Serial.print("Gas Value: ");
  Serial.println(gasValue);

  // While gas level is above threshold
  while (gasValue > threshold) {
    digitalWrite(ledPin, HIGH);
    Serial.println("⚠️ Gas Detected!");

    delay(500);

    // Read again inside while loop
    gasValue = analogRead(gasSensor);
    Serial.print("Gas Value: ");
    Serial.println(gasValue);
  }

  // Safe condition
  digitalWrite(ledPin, LOW);
  delay(500);
}