.nav-pills .dropdown {
    list-style: none;
    margin: 0;
    line-height: 24px;
    display: none;
    opacity: 0;
    transition: opacity .5s;
    position: absolute;
    background: #fff;
    width: 100%;
    text-align: center;
    border: 1px solid #eeeeee;
    z-index: 1000;
}
.nav-pills>li:hover {
    background-color: #eeeeee;
}
.nav-pills>li:hover .dropdown {
    display: block;
    opacity: 1;
}
.nav-pills .dropdown li:hover {
    background: #fafafa;
    cursor: pointer;
}
.nav-pills .dropdown li:hover a {
    text-decoration: none;
    display: block;
}