<script type="text/javascript">
window.onload = function () {
var nav = document.getElementById('nav');
var navFixed = document.getElementById('navFixed');
window.onscroll = function () {
var scrollTop = document.documentElement.scrollTop || document.body.scrollTop;
document.title = scrollTop
if (scrollTop > nav.offsetTop) {
navFixed.style.display = 'block';
} else if (scrollTop < nav.offsetTop) {
navFixed.style.display = 'none';
}
}
};
</script>
<style type="text/css">
.nav-wrapper{margin:5px auto;width: 960px;}
.nav-wrapper-fixed{ position:fixed; top:0; width:100%;margin:5px auto;width: 960px;z-index:999;}
</style>
<div class="nav-wrapper">
<a href=/pages/cyyw/2013/1204/402.html><img src="/uploads/allimg/131204/2_1141363141.png"></a>
</div>
<div class="cen">
<div class="nav-wrapper-fixed" id="navFixed" style="display:none;">
<a href=/pages/cyyw/2013/1204/402.html><img src="/uploads/allimg/131204/2_1141363141.png"></a>
</div>
</div>