function liuyan_close(){
	document.getElementById("liuyan_div").style.display="none"
}
function liuyan_show(){
	document.getElementById("liuyan_div").style.display="block"
	document.getElementById("liuyan_div").style.top=20+document.documentElement.scrollTop
}
function check_liuyan(){
	if(document.liuyan.liuyanvalue.value==""||document.liuyan.liuyanvalue.value.length>500){
		alert("ÁôÑÔÎª¿Õ»ò¹ý³¤")
		return false
	}
	liuyan_close()
	return true
}