if (window.navigator.userAgent.indexOf("MSIE")>=1)
{
var IE1024="ie768.css";
var IE1280="ie800.css";
var IE1440="ie900.css";
var IEother="ie800.css";

ScreenWidth(IE1024,IE1280,IE1440,IEother)
}else{
if (window.navigator.userAgent.indexOf("Firefox")>=1)
{
//如果浏览器为Firefox
var Firefox1024="ff768.css";
var Firefox1280="ff800.css";
var Firefox1440="ff900.css";
var Firefoxother="ff800.css";

ScreenWidth(Firefox1024,Firefox1280,Firefox1440,Firefoxother)
}else{
//如果浏览器为其他
var Other1024="ff768.css";
var Other1280="ff800.css";
var Other1440="ff900.css";
var Otherother="ff800.css";
ScreenWidth(Other1024,Other1280,Other1440,Otherother)
}
}

function ScreenWidth(CSS1,CSS2,CSS3,CSS4){
if ((screen.width == 1024) && (screen.height == 768)){
setActiveStyleSheet(CSS1);
}else{
if ((screen.width == 1280) && (screen.height == 800)){
setActiveStyleSheet(CSS2);
}else{
if ((screen.width == 1440) && (screen.height == 900)){
setActiveStyleSheet(CSS3);
}else{
setActiveStyleSheet(CSS4);
}}}
}

function setActiveStyleSheet(title){ 
  document.getElementById("skin").href=title; 
}