代码简介：貌似是老外写的，非常的流畅。
代码内容：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>JS+CSS动态平滑下拉菜单_网页代码站(www.webdm.cn)</title>
<style type="text/css">
body {cursor:crosshair; background:#111; margin:0; padding:0; position:absolute; overflow:hidden; left:0; top:0; 100%;
height:100%;}
.link {position:absolute;left:0;100%;height:0;background:#000;overflow:hidden;visibility:hidden;}
.title {position:relative;cursor:pointer;background:#333;100%;color:#fff;font-family:verdana;font-
size:11px;left:2;height:15;overflow:hidden;}
.title_o {position:relative;cursor:pointer;background:#fff;100%;color:#000;font-family:verdana;font-
size:11px;left:2;height:15;overflow:hidden;}
.text {position:relative;text-align:justify;margin:10px;font-family:verdana;font-size:11px;color:#FFF;overflow:hidden;height:90%}
</style>
<script type="text/javascript"><!--
var object = new Array();
function Slide(N,oCont){
this.N = N;
this.S = 1.1;
this.object = new Array();
this.CObj = function (parent,N){
this.parent = parent;
this.N = N;
this.obj = parent.frm[N];
this.tit = this.obj.firstChild;
this.div = this.obj.getElementsByTagName("div")[1];
this.div.style.visibility = "hidden";
this.y0 = N * 18;
this.Y1 = this.y0;
this.obj.style.top = this.y0;
this.obj.style.height = parent.H - (parent.NF-1) * 18 - 3;
this.obj.style.visibility = "visible";
this.obj.parent = this;
this.run = false;
this.move = function(){
with(this){
dy = (y1-y0)/parent.S;
if(Math.abs(dy)>.1){
y0+=dy;
obj.style.top = Math.round(y0);
setTimeout("object["+parent.N+"].object["+N+"].move();", 16);
} else {
run = false;
if(dy>0)div.style.visibility="hidden";
else if(N>0)parent.object[N-1].div.style.visibility="hidden";
}
}
}
this.obj.onmouseover = function(){
with(this.parent){
if(!run){
run = true;
div.style.visibility="visible";
for(i=0;i<parent.NF;i++)parent.object[i].tit.className = "title";
tit.className = "title_o";
for(i=0;i<=N;i++){
parent.object[i].y1 = i*18;
parent.object[i].move();
}
for(i=N+1;i<parent.NF;i++){
parent.object[i].y1 = parent.H-(parent.NF-i)*18;
parent.object[i].move();
}
}
}
}
}
this.frm = document.getElementById(oCont);
this.H = parseInt(this.frm.style.height);
this.frm = this.frm.getElementsByTagName("span");
this.NF = this.frm.length;
for(i=0;i<this.NF;i++) this.object[i] = new this.CObj(this, i);
this.object[0].obj.onmouseover();
this.S = 10;
}
onload = function() {
object[0] = new Slide(0, "frames");
}
//-->
</script>
</head>
<body>
<div style="position: absolute; left: 50%; top: 50%;">
<div id="frames" style="overflow: hidden; position: absolute; 200px; height: 340px; left: -100px; top: -170px;">
<span style="top: 0pt; height: 211px; visibility: visible;" class="link"><div class="title_o"></div>
<div style="margin: 20px; overflow: hidden; position: relative; text-align: center; font-family: verdana; font-size:
32px; font-weight: bold; color: rgb(255, 255, 255); height: 90%; visibility: visible;">
The Circle of Life
</div>
</span>
<span style="top: 213px; height: 211px; visibility: visible;" class="link"><div class="title">Programmer to Module
Leader:</div>
<div style="visibility: hidden;" class="text">
"This is not possible. **Impossible**. It will involve design change
and no body in our team knows the design of the system. And above that
nobody in our company knows the language in which this software has
been written. So even if somebody wants to work on it, they can't. If
you ask my personal opinion the company should never take these type of
projects." </div>
</span>
<span style="top: 231px; height: 211px; visibility: visible;" class="link"><div class="title">Module Leader to Project
Manager:</div>
<div style="visibility: hidden;" class="text">
"This project will involve design change. Currently we don't have
people who have experience in this type of work. Also the language is
unknown so we will have to arrange for some training if we take this
project. In my personal opinion, we should avoid taking this project." </div>
</span>
<span style="top: 249px; height: 211px; visibility: visible;" class="link"><div class="title">Project Manager to 1st Level
Manager:</div>
<div style="visibility: hidden;" class="text">
"This project involves design change in the system and we don't have
much experience in that area. Also not many people are trained in this
area. In my personal opinion we can take the project but we should ask
for some more time." </div>
</span>
<span style="top: 267px; height: 211px; visibility: visible;" class="link"><div class="title">1st Level Manager to 2nd Level
Manager:</div>
<div style="visibility: hidden;" class="text">
"This project involves design re-engineering. We have some people who
have worked in this area and some who know the language. So they can
train other people. In my personal opinion we should take this project
but with caution." </div>
</span>
<span style="top: 285px; height: 211px; visibility: visible;" class="link"><div class="title">2nd Level Manager to CEO:</div>
<div style="visibility: hidden;" class="text">
"This project will show the industry our capabilities in remodeling the
design of a complete system. We have all the necessary skills and
people to execute this project successfully. Some people have already
given in-house training in this area to other people. In my personal
opinion we should not let this project go by under any circumstance." </div>
</span>
<span style="top: 303px; height: 211px; visibility: visible;" class="link"><div class="title">CEO to Client:</div>
<div style="visibility: hidden;" class="text">
"These are the type of projects in which our company specialize. We
have executed many project of the same nature for many big clients.
Trust me when I say that you are in the safest hand in the Industry. In
my personal opinion we can execute this project successfully and that
too well with in the given time frame." </div>
</span>
<span style="top: 321px; height: 211px; visibility: visible;" class="link"><div class="title"></div>
<div style="margin: 20px; overflow: hidden; position: relative; text-align: center; font-family: verdana; font-size:
32px; font-weight: bold; color: rgb(255, 255, 255); height: 90%; visibility: hidden;">
The End
</div>
</span>
</div>
</div>
</body>
</html>
<br>
<p><a href="http://www.webdm.cn">网页代码站</a> - 最专业的代码下载网站 - 致力为中国站长提供有质量的代码！</p>
代码来自：http://www.webdm.cn/webcode/5d66c0f5-368c-47c7-b299-20d1fd1ce2b4.html