// Here is the method called on _TUTORIAL.PLAYING
    //
    void AboutPlay()
    {
        // if the bool _clickable is true on click the info changes
        // after a click starte the timeout with a _clickable = flase

        if (_clickable)
        {
            if (Input.GetMouseButtonDown(0))
            {
                _tutoInt  += 1;
                _clickable = false;
            }
        }

        // if int < 2 the text change
        // if > 2 TUTORIAL.GAMEOVER starts

        if (_tutoInt == 1)
        {
            ChangeText(1);
        }

        if (_tutoInt == 2)
        {
            ChangeText(2);
        }

        if (_tutoInt > 2)
        {
            _tutorial = _TUTORIAL.GAMEOVER;
        }
    }
    // START() is called on the beginning of the scene
    // here is displayed all the info for TUTORIAL.WELCOME
    void Start()
    {
        _TutorialHUD.SetActive(true);
        _GameHUD.SetActive(false);

        _tutorial = _TUTORIAL.WELCOME;
        _loading.gameObject.SetActive(true);
        ChangeText(0);
        _tutoInt       = 0;
        Time.timeScale = 0;

        if (Input.GetMouseButton(0))
        {
            _tutorial = _TUTORIAL.PLAYING;
        }
    }