var currentTextSize = null;
var currentLineHeight = null;
// check for cookie
if (get_text_cookie("fontsize")) {
    currentTextSize = parseInt(get_text_cookie("fontsize"));
} else {
    currentTextSize = 19;
    createCookie("fontsize",currentTextSize,1000);
}
currentLineHeight = currentTextSize + 5;

function textSize(dir) {
    if (dir == 'up') {
        if (currentTextSize <= 19) {
            currentTextSize += 2;
        }
    } else if (dir == 'down') {
        if (currentTextSize >= 11) {
            currentTextSize -= 2;
        }
    }
    currentLineHeight = currentTextSize + 5;
    document.getElementById('content').style.fontSize = currentTextSize + 'px';
    document.getElementById('content').style.lineHeight = currentLineHeight + 'px';
    // write/rewrite cookie
    createCookie("fontsize",currentTextSize,1000);
}

function get_text_cookie ( cookie_name )
{
  var results = document.cookie.match ( cookie_name + '=(.*?)(;|$)' );

  if ( results ) {
    return ( unescape ( results[1] ) );
  }
  else { return null; }
}