Pause Menu problem

I have a pause menu, but I can't seem to be able to access a way to put in the code necessary to check if the mouse is on a button or in the text of that button and send it an action if clicked on that (need event on mouseover, exit, up).

the code is as following: using System; using UnityEngine;

public class PauseMenu : MonoBehaviour { public static bool paused = false; public Texture menu; public Texture button; public Font Paused; public Font AllRest; Color LastColor;

 void OnGUI()
 {
     if (paused)
     {
         GUI.DrawTexture(new Rect(70, 45, 640, 480), menu, ScaleMode.ScaleToFit, true, 0.0f);
         LastColor = GUI.color;

         GUI.color = new Color(0.65f, 0.0f, 0.0f, 1.0f);
         GUI.skin.label.font = Paused;
         GUI.skin.label.fontSize = 150;

         GUI.Label(new Rect(260, 95, 300, 200), "Pausado");

         GUI.color = LastColor;

         GUI.DrawTexture(new Rect(95, 250, 580, 60), button, ScaleMode.ScaleToFit, true, 0.0f);
         GUI.DrawTexture(new Rect(95, 320, 580, 60), button, ScaleMode.ScaleToFit, true, 0.0f);
         GUI.DrawTexture(new Rect(95, 390, 580, 60), button, ScaleMode.ScaleToFit, true, 0.0f);

         GUI.color = new Color(0.65f, 0.0f, 0.0f, 1.0f);
         GUI.skin.label.font = AllRest;
         GUI.skin.label.fontSize = 37;

         GUI.Label(new Rect(250, 261, 300, 100), "Retornar ao Jogo");
         GUI.Label(new Rect(290, 331, 250, 100), "Salvar Jogo");
         GUI.Label(new Rect(260, 401, 300, 100), "Voltar ao Menu");
     }
 }

 public static bool togglePause()
 {
     if (Time.timeScale == 0f)
     {
         Time.timeScale = 1f;
         TP_Controller.CanMove = true;
         TP_Controller.isAttacking = false;
         return (false);
     }
     else
     {
         Time.timeScale = 0f;
         TP_Controller.CanMove = false;
         TP_Controller.isAttacking = true;
         return (true);
     }
 }

}