js彩蛋。。。

<script type="text/javascript">
    function trick(e){
        if(typeof window.k=="undefined"){
            window.k=""
        }
        var e=e||event;
        //alert(e.keyCode);
        if(e.keyCode==116) window.k="";
        window.k+=e.keyCode+",";
        if(window.k=="38,38,40,40,37,37,39,39,") {
            play();
            window.k="";
        }
    }
    function play(){
        alert('开启彩蛋模式');
       //更多精彩自己想象;
    }
    document.onkeydown=trick;
</script>