style.css

html {
    background:#018DED;
    background-size:cover;
    font-family:'helvetica neue';
    text-align: center;
    font-size: 10px;
}

body {
    margin: 0;
    font-size: 2rem;
    display:flex;
    flex:1;
    min-height: 100vh;
    align-items: center;
}

.clock {
    width: 30rem;
    height: 30rem;
    border:20px solid black;
    border-radius:50%;
    margin:50px auto;
    position: relative;
    padding:2rem;
    box-shadow:
            0 0 0 4px rgba(0,0,0,0.1),
            inset 0 0 0 3px #EFEFEF,
            inset 0 0 10px black,
            0 0 10px rgba(0,0,0,0.2);
}

.clock-face {
    position: relative;
    width: 100%;
    height: 100%;
    transform: translateY(-3px); /* account for the height of the clock hands */
}

.hand {
    width:50%;
    height:6px;
    background:black;
    position: absolute;
    top:50%;
    transform-origin: 100%;
    transform: rotate(90deg);
    transition: all 0.05s;
    transition-timing-function: cubic-bezier(0.1, 2.7, 0.58, 1);
}