void setup() {
  pinMode(3,OUTPUT); // red
  pinMode(9,OUTPUT); // green 
  pinMode(6,OUTPUT); // blue
  pinMode(7,INPUT); 
  Serial.begin(9600);
}


void loop() {
  Serial.println(digitalRead(7));
  if (digitalRead(7)==1){
    for (int i=0; i <= 255; i++) {
      analogWrite(3,i);
      analogWrite(6,i);
      analogWrite(9,i);
      delay(20);
      while (digitalRead==0) {
        sleep(10);
      }
    }
      for (int i=255; i >= 0; i--) {
      analogWrite(3,i);
      analogWrite(6,i);
      analogWrite(9,i);
      delay(20);
      while (digitalRead==0) {
        sleep(10);
      }
  
  }
  }
}