<script type='text/javascript'>
function CenterItem(theItem){
    var winHeight=$(window).height();
    var windowMiddle=winHeight/2;
    var itemMiddle=$(theItem).height()/2;
    var theMiddle=windowMiddle-itemMiddle;
    if(winHeight>$(theItem).height()){ //vertical
        $(theItem).css('top',theMiddle);
    } else {
        $(theItem).css('top','0');
    }
}

$(document).ready(function() {
    CenterItem('#second .bg');
});
$(window).resize(function() {
    CenterItem('#second .bg');
});

</script>

<div id="second">
      <div class="story"><div class="bg"></div>
      </div> <!--.story-->
</div> <!--#second-->

#second .bg{
    background: url(images/logo.png) 50% 0 no-repeat fixed ;
    height: 380px;
    margin: 0 auto;
    padding: 0;
    position: absolute;
    background-position: center center;
    width: 960px;
    z-index: 200;
}