JavaScript Clocks

Earlier this year, I created a JavaScript analogue clock for a side-project. The clock never made it into shipping code, so I thought I’d share it here for posterity.

The HTML is more complex than I might like:

<div class="clock-container">
    <div class="clock-body">
        <div class="clock-hours"></div>
        <div class="clock-center-shadow"></div>
        <div class="clock-minutes"></div>
        <div class="clock-center"></div>
        <div class="clock-seconds"></div>
        <div class="clock-center-seconds"></div>
    </div>
</div>

And, as always, the CSS is incredibly verbose:

.clock-container {
    background: #324B72;
    padding: 32px 0;
    margin: 0;
    border-radius: 6px;
    text-align: center;
}

.clock-body {
    display: inline-block;
    position: relative;
    height: 200px;
    width: 200px;
    border: 8px solid #fff;
    border-radius: 50%;
    box-shadow:
        0 0 5px rgba(0, 0, 0, 0.3),
        inset 0 0 5px rgba(0, 0, 0, 0.3);
    margin: 8px;
}

.clock-type-night {
    background-color: rgba(0, 0, 0, 0.3);
}

.clock-type-day {
    background-color: rgba(255, 255, 255, 0.3);
}

.clock-hours {
    box-sizing: border-box;
    background-color: #fff;
    position: absolute;
    width: 8px;
    height: 50px;
    border-radius: 4px;
    bottom: 96px;
    left: 96px;
    transform-origin: 4px 46px;
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
}

.clock-minutes {
    box-sizing: border-box;
    background-color: #fff;
    position: absolute;
    width: 6px;
    height: 80px;
    border-radius: 4px;
    bottom: 97px;
    left: 97px;
    transform-origin: 3px 77px;
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
}

.clock-center-shadow {
    position: absolute;
    width: 18px;
    height: 18px;
    background-color: #fff;
    border-radius: 50%;
    left: 91px;
    top: 91px;
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
}

.clock-center {
    position: absolute;
    width: 18px;
    height: 18px;
    background-color: #fff;
    border-radius: 50%;
    left: 91px;
    top: 91px;
}

.clock-seconds {
    box-sizing: border-box;
    background-color: #aaa;
    position: absolute;
    width: 2px;
    height: 100px;
    border-radius: 4px;
    bottom: 89px;
    left: 99px;
    transform-origin: 1px 89px;
    box-shadow: 0 0 5px rgba(0, 0, 0, 0.3);
}

.clock-center-seconds {
    position: absolute;
    width: 8px;
    height: 8px;
    background-color: #aaa;
    border-radius: 50%;
    left: 96px;
    top: 96px;
}

But at least the JavaScript is fairly simple:

$(document).ready(function() {

    var transform = function(degrees) {
        return "rotate(" + degrees + "deg)";
    }

    var updateTime = function() {

        var now = new Date();
        var hours = now.getHours();
        var minutes = now.getMinutes();
        var seconds = now.getSeconds();

        var hourDegrees = (hours * 30) + (minutes * 0.5);
        var minuteDegrees = ((minutes * 60) + seconds) * 0.1;
        var secondDegrees = (seconds * 6);

        $('.clock-hours').css("transform", transform(hourDegrees));
        $('.clock-minutes').css("transform", transform(minuteDegrees));
        $('.clock-seconds').css("transform", transform(secondDegrees));

    };

    setInterval(updateTime, 1000);
    updateTime();
});