html,
body {
    width: 100%;
    height: 100%;
}

body {
    width: 100%;
    height: 100%;
    padding: 0;
    margin: 0;
    overflow: hidden;
    font-size: 26px;
}

#rainbow {
    padding: 0;
    margin: 0;
    position: fixed;
    top: calc((100% - 141.4213562vmax) / 2);
    left: calc((100% - 141.4213562vmax) / 2);
    width: 141.4213562vmax;
    height: 141.4213562vmax;
    transform-origin: center;
    background: linear-gradient(-45deg, #11bff4, #e73c7e, #8211f4, #23d5ab);
    animation: gradient 15s linear infinite;
}

@keyframes gradient {
    0% {
        transform: rotate(0deg);
        filter: hue-rotate(0deg) saturate(78%) brightness(145%) contrast(200%);
    }

    50% {
        filter: saturation(64%) brightness(244%) contrast(100%);
    }

    100% {
        transform: rotate(360deg);
        filter: hue-rotate(360deg) saturate(78%) brightness(145%) contrast(200%);
    }
}


.hmm {
    animation: spin 45s infinite linear;
    z-index: 10;
    font-size: 160px;
}

@keyframes spin {
    0% {
        transform: rotate(360deg);
    }

    100% {
        transform: rotate(0deg);
    }
}

#center {
    display: flex;
    position: absolute;
    align-items: center;
    justify-content: center;
    z-index: 10;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    vertical-align: middle;
}