                        课程
                    
                        /前端开发
                        
                            /jQuery
                        
                        /jQuery基础课程

大神帮看下哪里出错了

<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
        <title>jQuery动画特效</title>
         <script src="http://libs.baidu.com/jquery/1.9.0/jquery.js" type="text/javascript"></script>
    </head>
    <style>
    body{
        position:relative;
        }
        div{
            width:50px;
            height:50px;
            background:red;
            position:absolute;
            left:150px;
            }

    </style>
    <body>
         <input type = button value="左移" id="mf"></input>
         <input type = button value="右移" id="mr"></input>
         <div></div>
    </body>
    <script>
        $(function(){
           $("#mf").bind("click",function(){
            $("div").animate({left:"50px"},100);
           }
            $("#mr").bind("click",function(){
            $("div").animate({right:"50px"},100);
           }
        })


    </script>
</html>