if (document.images) {
    img1 = new Image();
    img1.src = "./img/menu/1_on.png";
    img2 = new Image();
    img2.src = "./img/menu/2_on.png";
    img3 = new Image();
    img3.src = "./img/menu/3_on.png";
    img4 = new Image();
    img4.src = "./img/menu/4_on.png";
	img5 = new Image();
	img5.src = "./img/menu/5_on.png";

}