// 初期状態の値を設定
var defaultSize = "14px";

// クッキーの名前
var ckName = "longlife";

// クッキーの有効期限（日）
var ckDays = 2;

// クッキーのパス
var ckPath = "/"

// クッキー読み出し
var fsCK = GetCookie( ckName );

if ( fsCK == null ){
  var currentSize = defaultSize; 
} else {
  var currentSize = fsCK; 
}



document.writeln( '<style type="text/css">' );
document.write( 'body {font-size:' + currentSize + '; }' );
document.writeln( '</style>' );


function changeStyle( CMD ){

  if ( CMD == "large" ){
    SetCookie( ckName , CMD );          //クッキー書き込み
  }

  else if ( CMD == "small" ){
      SetCookie( ckName , CMD );          //クッキー書き込み
  }

  else {
      SetCookie( ckName , CMD );          //クッキー書き込み
  }
  location.reload();
}

/*===================================
  [関数 SetCookie]
  クッキーに値を書き込む
====================================*/
function SetCookie( name , value ){
  var dobj = new Date();
  dobj.setTime(dobj.getTime() + 24 * 60 * 60 * ckDays * 1000);
  var expiryDate = dobj.toGMTString();
  document.cookie = name + '=' + escape(value) + ';expires=' + expiryDate + ';path=' + ckPath;
}

/*===================================
  [関数 GetCookie]
  クッキーを取得する
====================================*/
function GetCookie (name){
  var arg  = name + "=";
  var alen = arg.length;
  var clen = document.cookie.length;
  var i = 0;
  while (i < clen){
    var j = i + alen;
    if (document.cookie.substring(i, j) == arg)
    return getCookieVal (j);
    i = document.cookie.indexOf(" ", i) + 1;
    if (i == 0) break;
  }
  return null;
}

/*===================================
  [関数 getCookieVal]
  クッキーの値を抽出する
====================================*/
function getCookieVal (offset){
  var endstr = document.cookie.indexOf (";", offset);
  if (endstr == -1)
  endstr = document.cookie.length;
  return unescape(document.cookie.substring(offset,endstr));
}

/*===================================
  [関数 DeleteCookie]
  クッキーを削除する
====================================*/
function DeleteCookie(name){
  if (GetCookie(name)){
    document.cookie = name + '=' +
    '; expires=Thu, 01-Jan-70 00:00:01 GMT;path='+ckPath;
  }
}