function menu_list_visible(id){
	document.getElementById("h_class_list_"+id).style.visibility="visible";
}
function menu_list_hidden(id){
	document.getElementById("h_class_list_"+id).style.visibility="hidden";
}

function change_content(value){
	document.getElementById("pa_content_0").className="pa_content";
	for (i=1;i<=3;i++){
		if(value==i){
			document.getElementById("pa_title_"+i).className="pa_title_on";
			document.getElementById("pa_content_"+i).className="pa_content_on";
		}else{
			document.getElementById("pa_title_"+i).className="pa_title";
			document.getElementById("pa_content_"+i).className="pa_content";
		}
    }

}