css push div down

    <style>
 div{border:1px solid red}
 #container{height:1000px;}
 #inner-container{position:absolute;bottom:0px;}
 .inner {height:200px;width:200px;margin:5px;;
</style>


<div id="container">
 <div id="inner-container">
  <div class="inner"></div>
  <div class="inner"></div>
  <div class="inner"></div>
 </div>
</div>