cRIRIc

function updateClock() {
    var dateFuture = new Date(new Date().getFullYear() + "-12-31 23:59:59");
    var dateNow = new Date();

    var seconds = Math.floor((dateFuture - (dateNow)) / 1000);
    var minutes = Math.floor(seconds / 60);
    var hours = Math.floor(minutes / 60);
    var days = Math.floor(hours / 24);

    hours = hours - (days * 24);
    minutes = minutes - (days * 24 * 60) - (hours * 60);
    seconds = seconds - (days * 24 * 60 * 60) - (hours * 60 * 60) - (minutes * 60);

    document.getElementById("days").innerHTML = "<span>" + days + "</span> Days";
    document.getElementById("hours").innerHTML = "<span>" + hours + "</span> hours";
    document.getElementById("minutes").innerHTML = "<span>" + minutes + "</span> minutes";
    document.getElementById("seconds").innerHTML = "<span>" + seconds + "</span> seconds";
}
setInterval(updateClock, 1000);

<div id="days"></div>
<div id="hours"></div>
<div id="minutes"></div>
<div id="seconds"></div>

div#countdown {
    border:1px solid #999;
    height:60px;
    text-align: center;
    padding:4px 0;
    background-color: #FFFAD3;
}
div#countdown div {
    float:left;
    padding:4px;
    color: #999;
    font-family: Courier;
    font-size: .9em;
    margin-left:3px;
}
div#countdown div span{
    display: block;
    background-color: #FFF;
    border:1px solid #999;
    padding:0;
    color: #000;
    font-size: 1.1em;
}