style.css

body {
    margin: 0;
    padding: 0;
    font-family: 'poppins', sans-serif;
}

html,
body {
    display: grid;
    height: 100vh;
    place-items: center;
    background: black;
}

.wrapper {
    height: 100px;
    width: 360px;
    cursor: default;
    background: linear-gradient(135deg, #14ffe9, #ffeb3b, #ff00e0);
    border-radius: 10px;
    animation: animate 1.5s linear infinite;
}

.display {
    position: absolute;
    top: 49%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 999;
    background: #1b1b1b;
    height: 85px;
    width: 345px;
    border-radius: 6px;
    text-align: center;
}

#clock {
    line-height: 85px;

    font-size: 45px;
    font-weight: 600;
    letter-spacing: 1px;
    background: linear-gradient(135deg, #14ffe9, #ffeb3b, #ff00e0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: animate 1.5s linear infinite;
}

@keyframes animate {
    100% {
        filter: hue-rotate(360deg);
    }
}