有没有办法让<div>和</div>紧靠在一起却能包含上面所有的内容？

window.onload = function(){
  document.getElementById("Lay1").innerHTML = "...";
}
<HTML>
<HEAD>
<Script language="javascript">
window.onload=function(){
document.getElementById('lay1').innerHTML=document.body.innerHTML
}
</Script>
</HEAD>
<body>...
test
test
test<br>
-------------------------------------------<br>
</body>
<div id=lay1></div>
</HTML>
document.getElementById('lay1').innerHTML=document.body.innerHTML