function alertinfo(id){
	var obj_str	=	"#"+id;
	var obj = $(obj_str);
	var W 	= screen.width;
	var H 	= screen.height;
	var yScroll;
	if (self.pageYOffset) {
		yScroll = self.pageYOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){
		yScroll = document.documentElement.scrollTop;
	} else if (document.body) {
		yScroll = document.body.scrollTop;
	}
	
	obj.css("top",(H/2 - 200　+　yScroll) + "px");
	$("#bg").css("display","block");
	obj.css("display","block");
	var scrollstyle = scrolls();
	scrollstyle.style.overflowX = "hidden";
	scrollstyle.style.overflowY = "hidden";
}

function closediv(id){
	var obj_str	=	"#"+id;
	//$("#bg").css("display","none");
	$(obj_str).css("display","none");
	
	var scrollstyle = scrolls();
	scrollstyle.style.overflowY = "auto";
	scrollstyle.style.overflowX = "hidden";
}
function scrolls(){
	var temp_h1 = document.body.clientHeight;
	var temp_h2 = document.documentElement.clientHeight;
	var isXhtml = (temp_h2<=temp_h1&&temp_h2!=0)?true:false;
	var htmlbody = isXhtml?document.documentElement:document.body;
	return htmlbody;
}