#mainmenu {
    height: 28px; /* need for eficient position*/
}
#mainmenu > ul > li {
    overflow: visible;
    display: block;
    float: left;
    white-space: nowrap;
}
#mainmenu > ul > li ul {
    display: none;
    position: absolute;
    background: #FFF;
    padding: 0;
    height: auto;
}
/* drop down menu */
#mainmenu > ul > li > ul {
    margin-top: 4px;

}
/* others sub menus */
#mainmenu > ul > li > ul li ul {
    margin-top: -20px; /* align with parent*/
    left:99%;
}

#mainmenu ul li:hover > ul {
    display: block;
}
#mainmenu ul li ul li a{
    padding: 4px 14px;
    background-color: #EFF4FA;
    color: #6399CD;
    text-decoration: none;
    display: block;
}
#mainmenu ul li ul li a:hover {
    color: #fff;
}