JavaScript实现新年倒计时效果

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>新年倒计时</title>
<link rel="stylesheet" href="style.css" rel="external nofollow"  />
</head>
 
<body>
<div class="time">距离新的一年还有 <span id="LeftTime"></span></div>
<script>
function FreshTime()
{
    var endtime=new Date("2017/1/28,00:00:00");//结束时间
    var nowtime = new Date();//当前时间
    var lefttime= parseInt((endtime.getTime()-nowtime.getTime())/1000) ; 
    d= parseInt(lefttime/(24*60*60)) ;
    h= parseInt(lefttime/(60*60)%24) ;
    m= parseInt(lefttime/60%60) ;
    s= parseInt(lefttime%60) ;
    
    document.getElementById("LeftTime").innerHTML=d+"天"+h+"小时"+m+"分"+s+"秒";
    if(lefttime<=0){
    document.getElementById("LeftTime").innerHTML="新年快乐";
    clearInterval(sh);
    }
}
  FreshTime()
  var sh;
  sh= setInterval(FreshTime,1000) ;
</script>
</body>
</html>

@charset "UTF-8";
/* CSS Document */
div{
 margin:0;
 padding:0;
 border:0;
}
 
 
.time{
 width:400px;
 height:30px;
 margin:30px auto;
 font-size:14px;
}
#LeftTime
{
  color:red;
}