style.css

.main {
    display: flex;
    padding: 2em;
    height: 90vh;
    justify-content: center;
    align-items: middle;
}

.clockbox,
#clock {
    width: 100%;
}

.circle {
    fill: none;
    
    stroke-width: 20;
    stroke-miterlimit: 10;
}

.mid-circle {
    fill: #000;
}
.hour-marks {
    fill: none;
    stroke: #000;
    stroke-width: 9;
    stroke-miterlimit: 10;
}

.hour-arm {
    fill: none;
    stroke: #000;
    stroke-width: 17;
    stroke-miterlimit: 10;
}

.minute-arm {
    fill: none;
    stroke: #000;
    stroke-width: 11;
    stroke-miterlimit: 10;
}

.second-arm {
    fill: none;
    stroke: #000;
    stroke-width: 4;
    stroke-miterlimit: 10;
}

.sizing-box {
    fill: none;
}

#hour,
#minute,
#second {
    transform-origin: 300px 300px;
    transition: transform .5s ease-in-out;
}