**style样式**
```
<style>
    .box{
        width:100px;
        height:100px;
        background-color:#ff9c69;
        font-size:20px;
        position:absolute;
        left:50px;
        text-align:center;
        line-height:100px;
        user-select:none;
    }
</style>
```

**文本内容**
```
<div class="box"></div>
<div class="box" style="background-color:red;margin-left:400px;"></div>
```

**js样式**
```
<script>
    var box=document.getElementsByClassName("box")[0];
    var box2=document.getElementsByClassName("box")[1];
    box.onmousedown=function(e){
        var ev=e||event;
        var divX=ev.offsetX;
        var divY=ev.offsetY;
        document.onmosuemvoe=function(){
            var ev=e||event;
            var x=ev.clientX-divX;
            var y=ev.clientY-divY;
            box.style.left=x+"px";
            box.style.top=y+"px";
            var moveL=box.offsetLeft;
            var moveR=box.offsetLeft+box.offsetWidth;
            var moveT=box.offsetTop;
            var moveB=box.offsetTop+box.offsetHeight;
            var hitL=box2.offsetLeft;
            var hitR=box2.offsetLeft+box2.offsetWidth;
            var hitT=box2.offsetTop;
            var hitB=box2.offsetTop+box2.offsetHeight;
            var r1=moveR>=hitL;
            var r2=moveL<=hitR;
            var r3=moveT<=hitB;
            var r4=moveB>=hitT;
            if(r1&&r2&&r3&&r4){
                box2.style.backgroundColor="red";
                box2.innerHTML="被撞了";
            }else{
                box2.style.backgroundColor="red";
                box2.innerHTML="";
            }
        }
    }
</script>
```

情况就是这样了。