$(document).ready(function(){
	initViewport();
	$("button#button_main_menu").click(buttonMainMenuClick);
	$("a#close_main_menu_button").click(hideMainMenu);
});

function initViewport() {
	var ww = ($(window).width() < window.screen.width) ? $(window).width() : window.screen.width;
	var mw = 600;
	var ratio = ww / mw;
	if (mw > ww) {
		$("#viewport").attr("content", "initial-scale=" + ratio + ", maximum-scale=" + ratio + ", minimum-scale=" + ratio + ", user-scalable=yes, width=" + ww);
	} else {
		$("#viewport").attr("content", "initial-scale=1.0, maximum-scale=2, minimum-scale=1.0, user-scalable=yes, width=" + ww);
	}
	
	var wh = $(window).height();
	wh = wh - 360 - 55;
	wh /= 2;
	$("div#main_menu_margin_top").css("height", wh+"px");
}

function buttonMainMenuClick() {
	$("div#main_menu_container").css("height", "100%");
	$("div#main_menu_container").css("visibility", "visible");
}

function hideMainMenu() {
	var main_menu_container = $("div#main_menu_container");
	main_menu_container.css("height", 0);
	main_menu_container.css("visibility", "hidden");
}