var date = new Date(2017, 3, 27, 21).getTime();
function countdown(milliseconds) {
    console.log(milliseconds);
    var CDDate = {
        seconds: 0,
        minutes: 0,
        hours: 0,
        days: 0
    }
    x = milliseconds / 1000;
    CDDate.seconds = Math.round(x % 60);
    x /= 60;
    CDDate.minutes = Math.round(x % 60);
    x /= 60;
    CDDate.hours = Math.round(x % 25);
    x /= 24;
    CDDate.days = Math.floor(x);
    return CDDate;
}

var diff = date - Date.now();
setInterval(function(){
    console.log(countdown(--diff));
},1000)