section {
    position: relative;
    width: 100%;
    height: 100vh;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

section .wave {
    position: absolute;
    left: 0;
    width: 100%;
    height: 100%;
    background: white;
    /* box-shadow: inset 0 0 50px rgba(0, 0, 0, 0.5); */
    transition: 0.5s;
}

section .wave span {
    content: "";
    position: absolute;
    width: 325vh;
    height: 325vh;
    top: 0;
    left: 50%;
    transform: translate(-50%, -75%);
    background: #000;
}

.content {
    position: relative;
    z-index: 1;
    font-size: 4em;
    color: #fff;
    text-align: center;
    margin: 400px;
    font-weight: 900;
    padding-bottom: 200px;
}

section .wave span:nth-child(1) {
    border-radius: 45%;
    background: rgba(20, 20, 20, 1);
    animation: animate 5s linear infinite;
}

section .wave span:nth-child(2) {
    border-radius: 40%;
    background: rgba(20, 20, 20, 0.5);
    animation: animate 10s linear infinite;
}

section .wave span:nth-child(3) {
    border-radius: 42.5%;
    background: rgba(20, 20, 20, 0.5);
    animation: animate 15s linear infinite;
}

@keyframes animate {
    0% {
        transform: translate(-50%, -75%) rotate(0deg);
    }

    100% {
        transform: translate(-50%, -75%) rotate(360deg);
    }
}