@media (max-width: 979px) {
    .nav-collapse {
        z-index: -1;
        position: fixed;
        top: 0px;
        left: 0px;
        width: 0px;
        height: 100%;
        background: #888;
        overflow: hidden;
    }
    .nav-collapse .nav {
        width: 160px;
        background: #BBB;
    }

    .nav-collapse .nav > li {
        border-top: 1px solid #DDD;
        border-bottom: 1px solid #999;
    }

    .nav-collapse .nav > li > a {
        color: #222;
    }

    .nav-collapse, .nav-collapse.collapse {
        height: 100%;
    }

    .nav-collapse {
        -webkit-transform: none;
    }
}