HTMLのrelative

<style type="text/css">
#test_div{
width: 100px;
height: 100px;
border: solid #000000 2px;
}
#test_div2{
width: 100px;
height: 100px;
border: solid #eaefaa 2px;
position: relative;
left: 100px;
top: -2px;
}
</style>
<div id="test_div">
<div id="test_div2">

</div>
</div>