Arduino dart trainer code

#include <TM1637Display.h>

const int CLK = 6;
const int DIO = 7;
const int buttonPin1 = 2;
const int buttonPin2 = 3;
const int buttonPin3 = 4;
const int resetPin = 5;

int buttonState1 = 0;
int buttonState2 = 0;
int buttonState3 = 0;
int resetState = 0;

TM1637Display display(CLK, DIO);

int score = 0;

void setup() {
  // put your setup code here, to run once:
  pinMode(buttonPin1, INPUT_PULLUP); // use internal pullup
  pinMode(buttonPin2, INPUT_PULLUP);
  pinMode(buttonPin3, INPUT_PULLUP);
  pinMode(resetPin, INPUT_PULLUP);
  display.setBrightness(0x0a);
  Serial.begin(9600);
}

void loop() {

  buttonState1 = digitalRead(buttonPin1);
  buttonState2 = digitalRead(buttonPin2);
  buttonState3 = digitalRead(buttonPin3);
  resetState = digitalRead(resetPin);
  if (buttonState1 == LOW) {
    score += 1;
    Serial.println(score);
    display.showNumberDec(score);
    delay(200);
  }
  if (buttonState2 == LOW) {
    score += 2;
    Serial.println(score);
    display.showNumberDec(score);
    delay(200);
  }
  if (buttonState3 == LOW) {
    score += 3;
    display.showNumberDec(score);
    delay(200);
  }
  if (resetState == LOW) {
    score = 0;
    Serial.println(score);
    display.showNumberDec(score);
    delay(200);
  }
  display.showNumberDec(score);
}