#main_image {
    margin: 0 auto;
    width:  676px;
    height: 240px;
    text-align: left;
    overflow: hidden;
    position: relative;
}
#main_image span {
    top:  0;
    left: 0;
    position: absolute;
	z-index:0;
}
#main_image span.main_image_first {
	z-index:10;
}