$(document).ready(function(){
	/** 
	 * show and hide the navi on the top
	 */
	$("#nav_edu").mouseover(function(){
			$('#nedu').show();
			$('#ntea').hide();
			$('#nstu').hide();
			$('#npar').hide();
			$("#Image28").attr("src","images/head_child/headzw01.jpg");
			$("#Image159").attr("src","images/head_child/head-xs-js01.jpg");
			$("#Image160").attr("src","images/head_child/head-xs-xs01.jpg");
			$("#Image161").attr("src","images/head_child/head-xs-jz01.jpg");
		});

	$("#nav_tea").mouseover(function(){
			$('#nedu').hide();
			$('#ntea').show();
			$('#nstu').hide();
			$('#npar').hide();
			$("#Image28").attr("src","images/head_child/headzw01_1.jpg");
			$("#Image159").attr("src","images/head_child/head-xs-js01_1.jpg");
			$("#Image160").attr("src","images/head_child/head-xs-xs01.jpg");
			$("#Image161").attr("src","images/head_child/head-xs-jz01.jpg");
		});

	$("#nav_stu").mouseover(function(){
			$('#nedu').hide();
			$('#ntea').hide();
			$('#nstu').show();
			$('#npar').hide();
			$("#Image28").attr("src","images/head_child/headzw01_1.jpg");
			$("#Image159").attr("src","images/head_child/head-xs-js01.jpg");
			$("#Image160").attr("src","images/head_child/head-xs-xs01_1.jpg");
			$("#Image161").attr("src","images/head_child/head-xs-jz01.jpg");
		});
	
	$("#nav_par").mouseover(function(){
			$('#nedu').hide();
			$('#ntea').hide();
			$('#nstu').hide();
			$('#npar').show();
			$("#Image28").attr("src","images/head_child/headzw01_1.jpg");
			$("#Image159").attr("src","images/head_child/head-xs-js01.jpg");
			$("#Image160").attr("src","images/head_child/head-xs-xs01.jpg");
			$("#Image161").attr("src","images/head_child/head-xs-jz01_1.jpg");
		});
})