File: themes/demo/assets/less/elements/navbar.less

.navbar-header .navbar-brand {
    padding-left: 55px;
    background-image: url('../images/winter.png');
    background-size: auto 60%;
    background-repeat: no-repeat;
    background-position: 7px 50%;
    transition: color 0.2s ease 0.05s;
    color: #ccc;
    &:hover {
        color: #fff;
    }
}

.navbar-nav li.separator {
    width: 1px;
    background: rgba(255, 255, 255, 0.3);
    height: 30px;
    margin: 20px 10px 0 10px;
}

.navbar-autohide {
    transition: transform .5s;
}

.navbar-autohide.is-hidden {
    transform: translateY(-(@navbar-height + 2px));
}

.navbar-collapse:not(.in):not(.collapsing) .navbar-nav li {
    > a {
        transition: color 0.2s ease 0.05s;
    }

    > a:after {
        position: absolute;
        height: 4px;
        bottom: -1px;
        content: '';
        border-radius: 4px;
        z-index: 5;
        width: 0;
        left: 50%;
        transition: all 0.2s ease 0.05s;
    }

    &.active > a:after {
        width: 100% !important;
        left: 0 !important;
    }

    &:hover > a:after {
        width: 100%;
        left: 0;
    }

    &.active > a {
        background: transparent;
    }
}

.navbar-inverse .navbar-collapse:not(.in):not(.collapsing) .navbar-nav li {
    &.active > a:after,
    > a:hover:after {
        background: @navbar-inverse-stripe-color-active;
    }

    &.active > a:hover:after {
        background: @navbar-inverse-stripe-color-active;
    }

    > a:hover:after {
        background: @navbar-inverse-stripe-color-hover;
    }
}

.navbar-default .navbar-collapse:not(.in):not(.collapsing) .navbar-nav li {
    &.active > a:after,
    > a:hover:after {
        background: @navbar-default-stripe-color-active;
    }

    &.active > a:hover:after {
        background: @navbar-default-stripe-color-active;
    }

    > a:hover:after {
        background: @navbar-default-stripe-color-hover;
    }
}