JS- Date 倒计时天数（初版）

        var t=new Date("2020,5,1");  //5.1   中国标准时间

        document.write(t+"<br>"); 

        var t1=t.getTime();          //毫秒

        document.write(t1+"<br>");

        var today = new Date();   //今天   中国标准时间

        document.write(today+"<br>");  

        var today1=today.getTime();   //毫秒

        document.write(today1+"<br>");   

        var leave = t1 - today1;

        var le=leave/1000/60/60/24;

        document.write(le); //24.11977929398148