Сначала у вас есть несколько ошибок PHP.Например,
<?php echo time(); ?>
Я использую метку времени в JavaScript для простоты показа примера.
http://jsfiddle.net/pimvdb/AvXd3/
// the difference timestamp
var timestamp = (Date.now() + 1000 * 60 * 60 * 24 * 3) - Date.now();
timestamp /= 1000; // from ms to seconds
function component(x, v) {
return Math.floor(x / v);
}
var $div = $('div');
setInterval(function() { // execute code each second
timestamp--; // decrement timestamp with one second each second
var days = component(timestamp, 24 * 60 * 60), // calculate days from timestamp
hours = component(timestamp, 60 * 60) % 24, // hours
minutes = component(timestamp, 60) % 60, // minutes
seconds = component(timestamp, 1) % 60; // seconds
$div.html(days + " days, " + hours + ":" + minutes + ":" + seconds); // display
}, 1000); // interval each second = 1000 ms