body {
    margin: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: lightyellow;
}

nav ul {
    padding: 0;
    list-style-type: none;
}

nav li {
    width: 8em;
    height: 2em;
    font-size: 25px;
    text-align: center;
    line-height: 2em;
    font-family: sans-serif;
    text-transform: capitalize;
    position: relative;
    transition: 0.5s;
    margin: 0.8em;
}

nav li::before,
nav li::after {
    content: '';
    position: absolute;
    width: 0.6em;
    height: 0.6em;
    background-color: gainsboro;
    border-radius: 50%;
    transition: 0.5s cubic-bezier(0.5, -0.5, 0.25, 1.5);
}

nav li::before {
    top: calc(50% - 0.6em / 2);
    left: 0;
    z-index: -1;
}

nav li::after {
    bottom: calc(50% - 0.6em / 2);
    right: 0;
    z-index: -2;
}

nav li:hover {
    color: white;
}

nav li:hover::before,
nav li:hover::after {
    width: 100%;
    height: 100%;
    border-radius: 0;
    background-color: dodgerblue;
}

nav li:hover::before {
    top: 0;
}

nav li:hover::after {
    bottom: -0.4em;
    right: -0.4em;
    filter: brightness(0.8);
}