String mycolour;
String msg1 = "colour?";
String msg2 = "colour is";
int green = 13;
int yellow = 12;
int red = 8;

void setup() {
  Serial.begin(9600);
  pinMode(green, OUTPUT);
  pinMode(yellow, OUTPUT);
  pinMode(red, OUTPUT);
}

void loop() {
  Serial.println(msg1);
  delay(100);

  while (Serial.available() == 0) {
    // Wait for input
  }
  mycolour = Serial.readString();
  mycolour.trim();  // Trim any extra characters like newline

  Serial.println(msg2);

  // Turn off all LEDs first
  digitalWrite(red, LOW);
  digitalWrite(green, LOW);
  digitalWrite(yellow, LOW);

  if (mycolour == "red") {
    digitalWrite(red, HIGH);
    Serial.println(mycolour);
  } else if (mycolour == "green") {
    digitalWrite(green, HIGH);
    Serial.println(mycolour);
  } else if (mycolour == "yellow") {
    digitalWrite(yellow, HIGH);
    Serial.println(mycolour);
  } else {
    Serial.println("Invalid colour");
  }

  delay(5000);  // Delay to keep LED on
}