const int pinR = 11;
const int pinG = 10;
const int pinB = 9;

void setup() {
  Serial.begin(9600);
  pinMode(pinR, OUTPUT);
  pinMode(pinG, OUTPUT);
  pinMode(pinB, OUTPUT);
}

void loop() {

  Serial.println("-------------------");
  while (!Serial.available()) {}
  String inputColor = Serial.readStringUntil('#');
  inputColor = Serial.readString();
  inputColor.trim();
  if (inputColor.length() > 6 || inputColor.length() < 6) {
    Serial.println("Wrong color");
  }

  if (inputColor.length() == 6) {
    Serial.println("Your color: #" + inputColor);
    String hex = inputColor;

    int redValue = strtol(hex.substring(0, 2).c_str(), NULL, 16);
    int greenValue = strtol(hex.substring(2, 4).c_str(), NULL, 16);
    int blueValue = strtol(hex.substring(4, 6).c_str(), NULL, 16);

    analogWrite(pinR, redValue);
    analogWrite(pinG, greenValue);
    analogWrite(pinB, blueValue);
  }

  delay(5000);
}