#define LED_PIN 9
#define INCREASE_BUTTON 2
#define DECREASE_BUTTON 3
#define STEP 26

int brightness = 0;

void setup() {
  pinMode(LED_PIN, OUTPUT);
  pinMode(INCREASE_BUTTON, INPUT_PULLUP);
  pinMode(DECREASE_BUTTON, INPUT_PULLUP);
  Serial.begin(9600);
  analogWrite(LED_PIN, brightness);  
}

void loop() {
  if (digitalRead(INCREASE_BUTTON) == LOW) {
    delay(50);  
    brightness += STEP;
    if (brightness > 255) {
      brightness = 255;
      Serial.println("Maxim");
    }
    analogWrite(LED_PIN, brightness);
  }

  if (digitalRead(DECREASE_BUTTON) == LOW) {
    delay(50);  // debounce
    brightness -= STEP;
    if (brightness < 0) {
      brightness = 0;
      Serial.println("Minim");
    }
    analogWrite(LED_PIN, brightness);
  }

  Serial.println(brightness);
  delay(100);
}