div.sub .box {
    position: relative;}

ul.sub2 {
    position: absolute;
    left: 100%;
    top: 0;
    background: #fff;
    width: 0;
    opacity:0;
    overflow:hidden;
    box-shadow: 0 0 60px rgba(0, 0, 0, .1);
    border-radius: 0 0 .05rem .05rem;
    transition: all 0.3s
;}

div.sub .box:hover ul.sub2 {
    opacity:1;
    overflow:visible;
    width:100%;
    min-width: 100%;}