ul.nav li > ul {
    margin-left: 17px !important;
    padding: 10px 20px !important;
    background-color: #222 !important;
    text-align: center !important;
    /*width: calc(100% - 34px);*/
}

ul.nav li > ul a {
    padding: 0 !important;
}

@media (max-width: 991px) {
    ul.nav li {
        position: relative;
    }

    ul.nav li > ul {
        display: block !important;
        position: relative !important;
        margin-left: 0 !important;
        background-color: transparent !important;
        width: auto;
    }
}