nav.shift3 ul li a {
    position: relative;
    z-index: 1;
}

nav.shift3 ul li a:hover {
    /* color: #000; */
    text-decoration: none;
    color: #fff;
}

nav.shift3 ul li a:after {
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    /* bottom: 0;
    right: 0; */
    margin: auto;
    width: 100%;
    height: 1px;
    content: '.';
    color: transparent;
    visibility: none;
    opacity: 0;
    z-index: -1;
    background-color: #668ee2;
}

nav.shift3 ul li a:hover:after {
    opacity: 1;
    visibility: visible;
    height: 100%;
}

nav ul li a,
nav ul li a:after,
nav ul li a:before {
    transition: all .5s;
}

nav ul li a:hover {
    /* color: #555; */
}