ul.menu li li:hover>ul{
    top:0;
    left:7em;
    width:7em;
    height:auto; 
}

ul.menu>li>ul li li{
    height:1.5rem;/* change the height for small device*/
}

ul.menu ul ul
{
    position: absolute;
    top: 0px;
    left: 7em; /* this equals the width of submenu plus padding*/
    background: #575a62;
    -webkit-border-radius: 15px;
    -moz-border-radius: 15px;
    border-radius: 15px;
    border:none;
}