(function($) {

        $.extend({

            tipsBox: function(options) {

                options = $.extend({

                    obj: null, //jq对象，要在那个html标签上显示

                    str: "+1", //字符串，要显示的内容;也可以传一段html，如: "<b style='font-family:Microsoft YaHei;'>+1</b>"

                    startSize: "12px", //动画开始的文字大小

                    endSize: "30px", //动画结束的文字大小

                    interval: 600, //动画时间间隔

                    color: "red", //文字颜色

                    callback: function() {} //回调函数

                }, options);

                $("body").append("<span class='num'>" + options.str + "</span>");

                var box = $(".num");

                var left = options.obj.offset().left + options.obj.width() / 2;

                var top = options.obj.offset().top - options.obj.height();

                box.css({

                    "position": "absolute",

                    "left": left + "px",

                    "top": top + "px",

                    "z-index": 9999,

                    "font-size": options.startSize,

                    "line-height": options.endSize,

                    "color": options.color

                });

                box.animate({

                    "font-size": options.endSize,

                    "opacity": "0",

                    "top": top - parseInt(options.endSize) + "px"

                }, options.interval, function() {

                    box.remove();

                    options.callback();

                });

            }

        });

    })(jQuery);

$.tipsBox({

      obj: $("#zans"),

      str: "+1",

      callback: function() {}

});