if (document.images) {

	homeOff = new Image
	homeOn = new Image
	productsOff = new Image
	productsOn = new Image
	contactOff = new Image
	contactOn = new Image
	coursesOff = new Image
	coursesOn = new Image
		
	homeOff.src = "images/home.gif"
	homeOn.src = "images/home-over.gif"
	productsOff.src = "images/products.gif"
	productsOn.src = "images/products-over.gif"
	contactOff.src = "images/contact.gif"
	contactOn.src = "images/contact-over.gif"
	coursesOff.src = "images/courses.gif"
	coursesOn.src = "images/courses-over.gif"
		
	}

else {
	homeOff = ""
	homeOn = ""
	productsOff = ""
	productsOn = ""
	contactOff = ""
	contactOn = ""
	coursesOff = ""
	coursesOn = ""
		
	document.home = ""
	document.products = ""
	document.contact = ""
	document.courses = ""
	
	}