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 void OnGUI() {
       if (ifDown) {
            Vector3 worldToScreen = Camera.main.WorldToScreenPoint(transform.position);
            GUIStyle style1 = new GUIStyle();
            style1.fontSize = 30;
            style1.normal.textColor = Color.red;
            Rect rec = new Rect(worldToScreen.x, Screen.height - worldToScreen.y, 400, 50);
            GUI.Label(rec, "123123", style1);
       }
    }