冠状动脉的解剖结构:急！！！！如何更改宽度？？？！！！

代码如下：
//菜单
var menuOffX=0 //菜单距连接文字最左端距离
var menuOffY=20 //菜单距连接文字顶端距离

var ie4=document.all&&navigator.userAgent.indexOf("Opera")==-1
var ns6=document.getElementById&&!document.all
function showmenu(e,vmenu,mod){
which=vmenu
menuobj=document.getElementById("popmenu")
menuobj.thestyle=menuobj.style
menuobj.innerHTML=which
menuobj.contentwidth=menuobj.offsetWidth
eventX=e.clientX
eventY=e.clientY
var rightedge=document.body.clientWidth-eventX
var bottomedge=document.body.clientHeight-eventY

if (rightedge<menuobj.contentwidth)
menuobj.thestyle.left=document.body.scrollLeft+eventX-menuobj.contentwidth+menuOffX
else
menuobj.thestyle.left=ie4? ie_x(event.srcElement)+menuOffX : ns6? window.pageXOffset+eventX : eventX

if (bottomedge<menuobj.contentheight&&mod!=0)
menuobj.thestyle.top=document.body.scrollTop+eventY-menuobj.contentheight-event.offsetY+menuOffY-23
else
menuobj.thestyle.top=ie4? ie_y(event.srcElement)+menuOffY : ns6? window.pageYOffset+eventY+10 : eventY

menuobj.thestyle.visibility="visible"
}

function ie_y(e){
var t=e.offsetTop;
while(e=e.offsetParent){
t+=e.offsetTop;
}
return t;
}
function ie_x(e){
var l=e.offsetLeft;
while(e=e.offsetParent){
l+=e.offsetLeft;
}
return l;
}

function highlightmenu(e,state){
if (document.all)
source_el=event.srcElement
while(source_el.id!="popmenu"){
source_el=document.getElementById? source_el.parentNode : source_el.parentElement
if (source_el.className=="menuitems"){
source_el.id=(state=="on")? "mouseoverstyle" : ""
}
}
}

function hidemenu(){if (window.menuobj)menuobj.thestyle.visibility="hidden"}
function dynamichide(e){if ((ie4||ns6)&&!menuobj.contains(e.toElement))hidemenu()}
document.onclick=hidemenu
document.write("<div class=menuskin id=popmenu onmouseover=highlightmenu(event,'on') onmouseout=highlightmenu(event,'off');dynamichide(event)></div>")
//菜单END

如何更改下拉菜单的宽度啊？？？