color help

import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
import java.awt.Color;

public class CardWorld  extends World
{
   private  Deck d;
   private Card [] hand=new Card[5];
   private int c=0;
   boolean keyCaptured=false;
   Question q;
   Info info;
    public CardWorld()
    {    
        // Create a new world with 20x20 cells with a cell size of 10x10 pixels.
        super(500,400,1);
        GreenfootImage bg=getBackground();
        bg.setColor(new Color(0,128,0));
        bg.fill();
        d=new Deck();
        d.shuffle();
        setUp();
    }