GUI Button Jagged Edges JavaScript

I want to make a GUI button with these three stages:

I tried importing their three background and writing the text in code like this:

With the code:

 #pragma strict
 var customSkin:GUISkin;
 //button width
 var buttonW:int = 100;
 //button height
 var buttonH:int = 50;
 
 //half of the screen width
 var halfScreenW:int;
 
 
 function OnGUI() {
     GUI.skin=customSkin;
     if(GUI.Button(Rect(halfScreenW-buttonW/2,460,buttonW,buttonH), "Play Game")){
         print("Loading game.");
         Application.LoadLevel("Game");
     }
 }
 
 function Start() {
     halfScreenW = Screen.width/2;
 }

However the button came out with jagged edges. I am not allowed to any more images so I will put a pic of it in the comments.