jQuery.fn.countDown = function(settings,to) {  settings = jQuery.extend({    startFontSize: '36px',    endFontSize: '12px',    duration: 1000,    startNumber: 10,    endNumber: 0,    callBack: function() { }  }, settings);  return this.each(function() {    //where do we start?    if(!to && to != settings.endNumber) { to = settings.startNumber; }    //set the countdown to the starting number    $(this).text(to).css('fontSize',settings.startFontSize);    //loopage    $(this).animate({      'fontSize': settings.endFontSize    },settings.duration,'',function() {      if(to > settings.endNumber + 1) {        $(this).css('fontSize',settings.startFontSize).text(to - 1). countDown(settings,to - 1);      }      else      {        settings.callBack(this);      }    });  });};/* sample usage//調用方法//$('#countdown').countDown({  startNumber: 10,  callBack: function(me) {    $(me).text('倒計時加載完畢').css('color','#090');  }});