function ShowAbout() {
	var scrW, scrH;  
	if(window.innerHeight && window.scrollMaxY) {    // Mozilla   
	scrW = window.innerWidth + window.scrollMaxX;    
	scrH = window.innerHeight + window.scrollMaxY;  
	} else if(document.body.scrollHeight > document.body.offsetHeight){    // all but IE Mac    
	scrW = document.body.scrollWidth;    
	scrH = document.body.scrollHeight;  
	} else if(document.body) { // IE Mac    
	scrW = document.body.offsetWidth;    
	scrH = document.body.offsetHeight;  
	}  
	
	var winW, winH;  
	if(window.innerHeight) { // all except IE   
	winW = window.innerWidth;    
	winH = window.innerHeight;  
	} else if (document.documentElement && document.documentElement.clientHeight) {    // IE 6 Strict Mode    
	winW = document.documentElement.clientWidth;     
	winH = document.documentElement.clientHeight;  
	} else if (document.body) { // other    
	winW = document.body.clientWidth;    
	winH = document.body.clientHeight;  
	}  // for small pages with total size less then the viewport  
	
	var pageW = (scrW<winW) ? winW : scrW;  
	var pageH = (scrH<winH) ? winH : scrH;

	var divheight=pageH; //document.body.offsetHeight;
	if (document.all) { //如果是IE浏览器则使用scrollTop属性
	document.getElementById("overlay").style.filter = "alpha(opacity=50)";
	document.getElementById("overlay").style.height = divheight;
	document.getElementById("lightbox").style.top    = document.documentElement.scrollTop + 500;
	} else { //如果是NetScape浏览器则使用pageYOffset属性
	document.getElementById("overlay").style.opacity = "0.5";
	document.getElementById("overlay").style.height  = divheight + "px";
	document.getElementById("lightbox").style.top     = window.pageYOffset + 500 + "px";
	}
	document.getElementById("overlay").style.display = "block";
    document.getElementById("lightbox").style.display = "block";
}

function ShowOK() {
    document.getElementById("overlay").style.display = "none";
    document.getElementById("lightbox").style.display = "none";
	if (document.title.indexOf("Yu Liu")!=-1){
		self.location="index_cn.htm";
	} else {
		self.location="index.htm";
	}
}

function ShowCancel() {
    document.getElementById("overlay").style.display = "none";
    document.getElementById("lightbox").style.display = "none";
}