.sf_blog_extra4 {
    height: 120px;
    min-height: 120px;
    width: 900px;
    border-top: 2px solid #fff;
    border-bottom: 4px #fff solid;
    background-image: url(images/header_image_1.jpg);
    background-repeat: no-repeat;
 }

 .sf_blog_extra4 span {
    float: right;
    height: 120px;
    min-height: 120px;
    width: 696px;
    background-image: url(images/header_image_2.jpg);
    background-repeat: no-repeat;
 }