const int numLeds = 5;
int ledPins[numLeds] = {D5, D4, D17, D16, D2};
int brightness[numLeds] = {0, 0, 0, 0, 0};
int fadeAmount = 5;

void setup() {
  Serial.begin(115200);

  for (int i = 0; i < numLeds; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  for (int i = 0; i < numLeds; i++) {
    brightness[i] += fadeAmount;

    if (brightness[i] <= 0 || brightness[i] >= 255) {
      fadeAmount = -fadeAmount;
    }

    analogWrite(ledPins[i], brightness[i]);
  }

  delay(50);
}