类似边框栏弹出

<div id="box"></div>

<style>
        #box{
            width: 300px;
            height: 200px;
            background-color: skyblue;
            position: absolute;
            left: -250px;
            top: 0;
            cursor: pointer;
        }
    </style>

<script>
            window.onload=function(){
                var box=document.getElementById("box");
                var box_left=-250;
                var times;
                var back_times;
                box.onmouseover=function(){
                    clearInterval(back_times);
                    clearInterval(times);
                    times=setInterval(function(){
                        box_left+=10;
                    box.style.left=box_left+‘px‘;
                    if(box_left>=0){
                        clearInterval(times);
                    }
                    },10)
                }
                box.onmouseout=function(){
                    clearInterval(times)
                    clearInterval(back_times);
                    back_times=setInterval(function(){
                        box_left-=10;
                        box.style.left=box_left+‘px‘;
                        if(box_left<=-250){
                            clearInterval(back_times);
                        }
                    },10)
                }
            }
    </script>