Automatically pop-up navigation window

<style> .aa{height:2000px;width:40px;background:#eee;} .bb{width:50px;height:80px;background:red;float:right; position:fixed !important; top/**/ :0px; position:absolute; z-index:100; top:expression(offsetParent.scrollTop+20);right:20px; </style> <div class="aa"> I am not moving. <script>for(var i=0;i<99;i++){document.write(i+"<br>");}</script> <div class="bb">move</div> </div >