JS计算当年还有多少天

function counter() { 
  var date = new Date(); 
  var year = date.getFullYear(); 
  var date2 = new Date(year, 11, 30, 23, 59, 59,999);//
  /*转换成秒*/
  var time = (date2 - date) / 1000; 
  var day = Math.floor(time / (24 * 60 * 60)) 
  var hour = Math.floor(time % (24 * 60 * 60) / (60 * 60)) 
  var minute = Math.floor(time % (24 * 60 * 60) % (60 * 60) / 60); 
  var second = Math.floor(time % (24 * 60 * 60) % (60 * 60) % 60); 
  var str = year + "年还剩" + day + "天" + hour + "时" + minute + "分" + second + "秒"; 
  console.log(str); 
} 
window.setInterval("counter()", 1000);