function SetCookie(name,value)//两个参数，一个是cookie的名子，一个是值
{
    var Days = 300; //此 cookie 将被保存 30 天
    var exp  = new Date();    //new Date("December 31, 9998");
    exp.setTime(exp.getTime() + Days*24*60*60*1000);
    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();
}
function getCookie(name)//取cookies函数        
{
    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
     if(arr != null) return unescape(arr[2]); return null;
}
function delCookie(name)//删除cookie
{
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}
//SetCookie ("xiaoqi", "3");
//alert(getCookie('xiaoqi'));


function getcss(){
//设置页面css	
return getCookie("pv800css");
}

function savecss(cssindex){
SetCookie("pv800css",cssindex);
return;
}

function setcss(cssindex){
	switch (cssindex){
		case 1://样式2
		    document.getElementById("banner").href="./css/banner.css";
			document.getElementById("topcss_").href="./css/top.css";
			document.getElementById("stylecss_").href="./css/style.css";
			document.getElementById("copycss_").href="./css/copy.css";
			//document.getElementById("y2").src="./images/y2_1.jpg";
			//document.getElementById("y3").src="./images/y3.jpg";
			//document.getElementById("y4").src="./images/y4_1.jpg";			
			break;
		
		case 2://样式3
		    document.getElementById("banner").href="./css/jh_banner.css";
			document.getElementById("topcss_").href="./css/j_top.css";
			document.getElementById("stylecss_").href="./css/j_style.css";
			document.getElementById("copycss_").href="./css/copy.css";
			//document.getElementById("y2").src="./images/y2.jpg";
			//document.getElementById("y3").src="./images/y3_1.jpg";
			//document.getElementById("y4").src="./images/y4_1.jpg";
			break;
		
		case 3://样式4
		    document.getElementById("banner").href="./css/sl_banner.css";
			document.getElementById("topcss_").href="./css/l_top.css";
			document.getElementById("stylecss_").href="./css/l_style.css";
			document.getElementById("copycss_").href="./css/copy.css";
			//document.getElementById("y2").src="./images/y2.jpg";
			//document.getElementById("y3").src="./images/y3.jpg";
			//document.getElementById("y4").src="./images/y4.jpg";
			break;
		default:
			break;
	}
	savecss(cssindex);
	return;	
}

function app_css(){
setcss(getcss()/1);
return;
}
app_css();//立即生效