<div id="countdown-timer"
 data-time="<?php echo $bus->getStartDateTime()->format('M d, Y H:i:s'); ?>" >

var countdownTimer = $("#countdown-timer"),
        countDownDate = new Date(countdownTimer.data('time')).getTime();

    var intervalId = setInterval(function() {

        var now = new Date().getTime();
        var distance = countDownDate - now;

        var days = Math.floor(distance / (1000 * 60 * 60 * 24)),
            hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60)),
            minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60)),
            seconds = Math.floor((distance % (1000 * 60)) / 1000);

        var remainingTime;

        var formatTime = function (count, label) {
            return "<span>" + count + "</span> <sub>" + _t(label) + ".</sub>"
        }

        if (days > 0) {
            remainingTime = formatTime(days, 'd') + ' ' + formatTime(hours, 'h') + ' ' + formatTime(minutes, 'm');
        } else if (days === 0 && hours !== 0 && minutes !== 0) {
            remainingTime = formatTime(hours, 'h') + ' ' + formatTime(minutes, 'm') + ' ' + formatTime(seconds, 's');
        } else if (days === 0 && hours === 0 && minutes !== 0) {
            remainingTime = formatTime(minutes, 'm') + ' ' + formatTime(seconds, 's');
        } else if (days === 0 && hours === 0 && minutes === 0) {
            remainingTime = formatTime(seconds, 's');
        } else {
            clearInterval(intervalId);
            remainingTime = '<div class="countdown-timer">' + formatTime(0, 'h') + ' ' + formatTime(0, 'm') + '</div>';
        }

        $('#countdown-timer').html(function() {
            $('#countdown-timer span.nbsp').remove();
            return remainingTime;
        });

    }, 1000);