menu14.css

body{
    margin: 0;
    padding: 0;
    font-family: sans-serif;
}
ul{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    display: flex;
    margin: 0;
    padding: 0;
}
ul li{
    list-style: none;
}
ul li a{
    position: relative;
    display: block;
    padding: 10px 20px;
    margin: 20px 0;
    text-transform: uppercase;
    text-decoration: none;
    color: #262626;
    font-weight: bold;
    transition: .5s;
    z-index: 1  
}
ul li a:hover{
    color: #fff;
}
ul li a:before{
    content: "";
    position: absolute;
    top: 0;
    left: 0%;
    width: 100%;
    height: 100%;
    border-top: 1px solid #000;
    border-bottom: 1px solid #000;
    transform: scaleY(2);
    opacity: 0;
    transition: .5s;
}
ul li a:hover:before{
    transform: scaleY(1.2);
    opacity: 1;
}
ul li a:after{
    content: "";
    position: absolute;
    top: 1px;
    left: 0%;
    width: 100%;
    height: 100%;
    background-color: #000;
    transform: scale(0);
    opacity: 0;
    transition: .5s;
    z-index:-1
}
ul li a:hover:after{
    transform: scale(1);
    opacity: 1;
}