https://subemisionero.com.ar/complementos/countdowntime/countdowntime.js

1(function ($) {
2    "use strict";
3
4    function getTimeRemaining(endtime) { 
5      var t = Date.parse(endtime) - Date.parse(new Date());
6      var seconds = Math.floor((t / 1000) % 60);
7      var minutes = Math.floor((t / 1000 / 60) % 60);
8      var hours = Math.floor((t / (1000 * 60 * 60)) % 24);
9      var days = Math.floor(t / (1000 * 60 * 60 * 24));
10      return {
11        'total': t,
12        'days': days,
13        'hours': hours,
14        'minutes': minutes,
15        'seconds': seconds
16      };
17    }
18
19    function initializeClock(id, endtime) { 
20      var daysSpan = $('.days');
21      var hoursSpan = $('.hours');
22      var minutesSpan = $('.minutes');
23      var secondsSpan = $('.seconds');
24
25      function updateClock() { 
26        var t = getTimeRemaining(endtime);
27
28        daysSpan.html(t.days);
29        hoursSpan.html(('0' + t.hours).slice(-2));
30        minutesSpan.html(('0' + t.minutes).slice(-2));
31        secondsSpan.html(('0' + t.seconds).slice(-2))
32
33        if (t.total <= 0) {
34          clearInterval(timeinterval);
35        }
36      }
37
38      updateClock();
39      var timeinterval = setInterval(updateClock, 1000);
40    }
41
42    var deadline = new Date(Date.parse(new Date()) + 25 * 24 * 60 * 60 * 1000 + 13 * 60 * 60 * 1000); 
43    initializeClock('clockdiv', deadline);
44
45})(jQuery);