How can I change GUI Label text size?

sorry guys. I asked it somewhere else but I didn't get the answer... I want to get larger size text... can I do anything with this order?

 using UnityEngine;
 using System.Collections;
 
 public class WarningArea : MonoBehaviour
 {
     string message = "";
 
     void OnTriggerEnter(Collider otherObjective)
     {
         if (otherObjective.tag == "MainCamera")
         {
             audio.Play();
             message = "Warning text or something!";
         }
     }
     
     void OnTriggerExit(Collider other)
     {
         message = "";
     }
     
     void OnGUI()
     {
         GUI.Label(new Rect(0, 0, 200, 20), message);
     }
 }