// JavaScript Document
function set_opacity(obj, opac){
	obj.style.filter='alpha(opacity="'+ opac +'")';
	obj.style.opacity = opac / 100;
	obj.style.MozOpacity = opac / 100;
}

function fade_in(fade_obj){
	spead = 1.5;
	page_obj = document.getElementById("page");
	if(window.now_opac == 0){
		window.now_opac = 1;
		fade_obj.style.display = "block";
	}else if(window.now_opac >= 100){
		clearInterval(fade_effect);
		window.now_opac = 100;
		set_opacity(page_obj, 0)
		page_obj.style.visibility = "visible";
	}else{
		window.now_opac *= spead;
	}
	set_opacity(fade_obj, window.now_opac);
	set_opacity(page_obj, 100 - window.now_opac);
	return;
}

function fade_out(fade_obj){
	spead = 10;
	page_obj = document.getElementById("page");
	if(window.now_opac <= 0){
		clearInterval(fade_effect);
		fade_obj.style.display = "none";
		window.now_opac = 0;
	}else{
		window.now_opac -= spead;
	}
	set_opacity(fade_obj, window.now_opac);
	set_opacity(page_obj, 100 - window.now_opac);
	return;
}

function open_item(elem_id){
	fade_obj = document.getElementById(elem_id);
	window.now_opac = 0;
//	set_opacity(fade_obj, 100);
	fade_effect = setInterval('fade_in(fade_obj)', 50);
}

function close_item(elem_id){
	fade_obj = document.getElementById(elem_id);
	window.now_opac = 100;
//	set_opacity(fade_obj, 100);
	fade_effect = setInterval('fade_out(fade_obj)', 10);
}