Chạy lại

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;
using TMPro;

public enum GameState { Playing, GameOver }

public class GameManager : MonoBehaviour
{
    public static GameManager Instance;

    public float speed = 10f;
    public float speedUp = 0.5f;
    public float maxSpeed = 20f;
    public TMP_Text distanceText;
    public GameObject gameOverPanel;
    public Button restartButton;
    public GameState state = GameState.Playing;
    private float distance;

    void Awake()
    {
        Instance = this;
    }

    void Update()
    {
        if (state != GameState.Playing) return;

        speed = Mathf.Min(speed + speedUp * Time.deltaTime, maxSpeed);
        distance += speed * Time.deltaTime;
        distanceText.text = "Distance: " + Mathf.FloorToInt(distance) + " m";
    }

    public void GameOver()
    {
        state = GameState.GameOver;
        speed = 0f;
        gameOverPanel.SetActive(true);
    }
}