div issue with position:absolute - html

Question

I want to place one div over the other. I've already accomplished this with position:absolute;, but the behavior is different on other screen resolutions—specifically, the div on top moves to the left. Can anyone figure out the issue? To better understand my question, see this page.
My CSS:
#flashplayercontainer{
overflow: auto;
}
#flashplayer{
width: 975px;
margin: 0 auto;
background-color:#666666;
border:#CC0000 thick 2px;
}
#adsbox{
background: #222;
width: 930px;
height: 480px;
position: absolute;
top: 350px;
left: 205px;
}
#cpmbox{
margin: 0 auto;
margin-top: 40px;
width: 500px;
text-align: center;
}
#cpmbox h2{
color: #FFF;
margin-bottom: 20px;
}
#cpmbox a {
color: #FC0;
cursor: pointer;
}
</style>
My HTML:
<div id="flashplayercontainer">
<div id="flashplayer">
...
</div>
<div id="adsbox" style="height: 400px;">
<div id="cpmbox">
<h2>Loading.......</h2>
<script type="text/javascript">document.write("<iframe src='http://www.epicgameads.com/ads/banneriframe.php?id=yeA5z58737&t=300x250&channel=2&cb=" + (Math.floor(Math.random()*99999) + new Date().getTime()) + "' style='width:300px;height:250px;' frameborder='0' scrolling='no'></iframe>");</script>
<p><a id="closeads">Close This Ads (<span id="covertimer">20</span>)</a></p>
</div>
</div>
</div>
</div>

Answer 1

Replace your css. we need to make it Position % with two div equally, I think its working perfectly.
#flashplayercontainer{
overflow: auto;
}
#flashplayer{
width: 975px;
margin: 0 auto;
}
#adsbox, #cpmbox {
width: 930px;
height: 480px;
border:#CC0000 thick 2px;
}
#adsbox {
bottom: 50%;
right: 50%;
position: absolute;
}
#cpmbox {
left: 50%;
position: relative;
background-color:#666666;
top: 50%;
margin: 0 auto;
margin-top: 40px;
text-align: center;
}
#cpmbox h2{
color: #FFF;
margin-bottom: 20px;
}
#cpmbox a {
color: #FC0;
cursor: pointer;
}

Answer 2

Three Things you need to change you code.
1) Make it Fixed instead of absolute
2) Left and Top make it % instead of px
like that:
#adsbox{
background: #222;
width: 930px;
height: 480px;
position: fixed;
top: 20%;
left: 15%;
}
3) If you want also minimize and Maximize (window resizing) time. you have to write JS for
position calculation of the Div i mean (left,top)
I hope its use full.

Answer 3

Please add the position:relative to flashplayercontainer div,
example:
#flashplayercontainer{
overflow: auto;
position:relative;
}
And do the some pixels adjust for top and left in ID adsbox.