//初期設定
var btNum;
var cookie_num;


function get_cookie(){
	btNum = document.cookie;
	
	cookie_num = btNum.indexOf("string=");
	if(cookie_num == -1 ){
		btNum = 1;	
	}
	else{
		cookie_num += 7;
		btNum = btNum.charAt(cookie_num);
	}
}


//初期化
function init(){
	get_cookie();

	if(btNum == "0"){
		 img_change(0);
		 navi_change(0);
	}
	else if(btNum == "1"){
		 img_change(1);
		 navi_change(1);
	}
	else if(btNum == "2"){
		 img_change(2);
		 navi_change(2);
	}
	else{
		Cookie_check();
		 img_change(1);
		 navi_change(1);
		 btNum = document.cookie = "string = 1; path=/;";
	}
	return false;
}


//クッキーからボタン切り替え
function navi_change(aname){
	if(aname == 0){
		btNum = document.cookie = "string = 0; path=/;";
	}
	else if(aname == 1){
		btNum = document.cookie = "string = 1; path=/;";
	}
	else if(aname == 2){
		btNum = document.cookie = "string = 2; path=/;";
	}
	return false;
}



//画像切り替え
function img_change(img_name){
	if(img_name == 0){
	document.letter_btn1.src="http://www.matsu-akira.com/images/btn_letter_s_ov.gif";
	document.letter_btn2.src="http://www.matsu-akira.com/images/btn_letter_m.gif";
	document.letter_btn3.src="http://www.matsu-akira.com/images/btn_letter_l.gif";
	}
	else if(img_name == 1){
	document.letter_btn1.src="http://www.matsu-akira.com/images/btn_letter_s.gif";
	document.letter_btn2.src="http://www.matsu-akira.com/images/btn_letter_m_ov.gif";
	document.letter_btn3.src="http://www.matsu-akira.com/images/btn_letter_l.gif";
	}
	else if(img_name == 2){
	document.letter_btn1.src="http://www.matsu-akira.com/images/btn_letter_s.gif";
	document.letter_btn2.src="http://www.matsu-akira.com/images/btn_letter_m.gif";
	document.letter_btn3.src="http://www.matsu-akira.com/images/btn_letter_l_ov.gif";
	}
	return false;
}



//クッキーチェック
function Cookie_check(){
	var flag = navigator.cookieEnabled;
	if (flag != true)
	{	
		alert("クッキーは無効になっております。クッキーを有効にして下さい。");
	}
}



//フォントサイズ
var txtsize = new Array();
var txtsize_default = 1;
txtsize[0] = '10px';
txtsize[1] = '12px';
txtsize[2] = '14px';

function settextsize(){
	get_cookie();
	document.write('<style type="text/css">');
	document.write('body,h1,h2,h3,h4,p { font-size:' + txtsize[btNum] + '; }');
	document.write('</style>');
}