ul {
    background-color: darkslategray;
    list-style-type: none;
    margin: 0px;
    padding: 5px;
    overflow: hidden;
}

ul li {
    float: left;
}

ul li a {
    display: block;
    color: azure;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
    margin-left: 10px;
    margin-right: 10px;
    font-weight: 700;
}

ul li a.active {
    color: darkslategray;
    background-color: azure;
    border-bottom-right-radius: 20px;
    border-top-left-radius: 30px;
}

ul li a:hover {
    background-color: greenyellow;
    color: darkslategray;
    border-bottom-left-radius: 20px;
    border-top-right-radius: 30px;
}

ul li a.active:hover {
    border-bottom-left-radius: 0px;
    border-top-right-radius: 0px;
}