<div id="index_head">
<div id="tou">
</div>
<div id="menu">
<div id="menu_a">
<div class="list" onmouseover="show('xizang')" onmouseout="hide('xizang')">
<a href="xibeifengguang.html">西藏</a>
</div>
<div class="erji">
<div class="erwai" id="xizang" onmouseover="xianshi(this)" onmouseout="yincang(this)">
<div class="item">
<a href="linzhi.html"> 林芝</a>
</div>
<div class="item">
<a href="budalagong.html">布达拉宫</a>
</div>
<div class="item">
<a href="namucuo.html">纳木错</a>
</div>
</div>
</div>
<div class="list" onmouseover="show('qinghai')" onmouseout="hide('qinghai')">
<a href="xibeifengguang.html">青海</a>
</div>
<div class="erji">
<div class="erwai" id="qinghai" onmouseover="xianshi(this)" onmouseout="yincang(this)">
<div class="item">
<a href="qinghaihu.html">青海湖</a>
</div>
<div class="item">
<a href="nianbaoyuze.html">年宝玉则</a>
</div>
</div>
</div>
<div class="list" onmouseover="show('gansu')" onmouseout="hide('gansu')">
<a href="xibeifengguang.html">甘肃</a>
</div>
<div class="erji">
<div class="erwai" id="gansu" onmouseover="xianshi(this)" onmouseout="yincang(this)">
<div class="item">
<a href="jiayuguan.html">嘉峪关</a>
</div>
<div class="item">
<a href="danxia.html">张掖丹霞</a>
</div>
<div class="item">
<a href="mingshashan.html">鸣沙山</a>
</div>
<div class="item">
<a href="mogaoku.html">莫高窟</a>
</div>
</div>
</div>
<div class="list" onmouseover="show('xinjiang')" onmouseout="hide('xinjiang')">
<a href="xibeifengguang.html">新疆</a>
</div>
<div class="erji">
<div class="erwai" id="xinjiang" onmouseover="xianshi(this)" onmouseout="yincang(this)">
<div class="item">
<a href="tianshan.html">天山天池</a>
</div>
<div class="item">
<a href="kanasi.html">喀纳斯湖</a>
</div>
<div class="item">
<a href="nalati.html">那拉提</a>
</div>
</div>
</div>
</div>
</div>
</div>
window.onscroll = function(){
if(window.scrollY>=200){
document.getElementById("menu").style.position = "fixed";
document.getElementById("menu").style.top = "0px";
}else{
document.getElementById("menu").style.position = "";
}
}
function show(id){
var d = document.getElementById(id);
d.style.display = "block";
}
function hide(id){
var d = document.getElementById(id);
d.style.display = "none";
}
function xianshi(d){
d.style.display = "block";
}
function yincang(d){
d.style.display = "none";
}