@keyframes NavItem {
    0% {
        width: 0;
    }

    100% {
        width: 100%;
    }
}

#navbar {
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    z-index: 9999;
}

.navbar-nav a {
    color: #fff;
}

.navbar-nav .cur a {
    color: #fff;
}

.navbar-nav .cur::after {
    display: block !important;
}

.navbar-nav .nav-item a {
    transition: 500ms;
}

.navbar-nav .nav-item {
    position: relative;
}

.navbar-nav .nav-item:hover::after {
    display: block;
}

.navbar-nav .nav-item::after {
    content: '';
    width: 0;
    height: 2px;
    background-color: #fff;
    position: absolute;
    bottom: -31px;
    display: none;
    animation: NavItem 500ms forwards;
}