String comparision

String myColor;
String yellowColor="yellow";
String blueColor="blue";
String greenColor="green";

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(9,OUTPUT);
  pinMode(10,OUTPUT);
  pinMode(11,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(9, LOW);
  digitalWrite(10, LOW);
  digitalWrite(11, LOW);
  
  Serial.println("Enter the color you want to display : ");
  while (!Serial.available()) {
  }
  
  myColor = Serial.readString();
  Serial.print(myColor);

  if (myColor.equals(yellowColor)) {
    digitalWrite(9,HIGH);
    digitalWrite(10,LOW);
    digitalWrite(11,LOW);
    Serial.println("I am Yellow");
  } 
  
  if (myColor.equals(blueColor)) {
    digitalWrite(9,LOW);
    digitalWrite(10,HIGH);
    digitalWrite(11,LOW);
    Serial.println("I am Blue");
  } 
  
  if (myColor.equals(greenColor)) {
    digitalWrite(9,LOW);
    digitalWrite(10,LOW);
    digitalWrite(11,HIGH);
    Serial.println("I am Green");
  }
}