.clock_face {
    width: 100px;
    height: 100px;
    background-image: url('../image/test/clock_face.png');
    position: relative;
}
.clock_hours,
.clock_minutes,
.clock_seconds {
    width: 100px;
    height: 100px;
    position: absolute;
    top: 0;
    left: 0;
}