countdown.js

var remain_bv   = 1200; //секунд
function timeLeft(timestamp){
    if (timestamp < 0) timestamp = 0;
 
    var day = Math.floor( (timestamp/60/60) / 24);
    var hour = Math.floor(timestamp/60/60);
    var mins = Math.floor((timestamp - hour*60*60)/60);
    var secs = Math.floor(timestamp - hour*60*60 - mins*60); 
    var left_hour = Math.floor( (timestamp - day*24*60*60) / 60 / 60 );     
}