function getNextStyleSheet(title) {
	if (title == 'normal' || title == 'normal2') { document.getElementById("vergroessern").title = "gross"; 	document.getElementById("kleiner_img").src = "image/all/minus_grau.gif"; 	document.getElementById("groesser_img").src = "image/all/plus.gif"; }
	if (title == 'gross' )						 { document.getElementById("vergroessern").title = "groesser"; 	document.getElementById("kleiner_img").src = "image/all/minus.gif";			document.getElementById("groesser_img").src = "image/all/plus.gif";  }
	if (title == 'groesser' )					 { document.getElementById("vergroessern").title = "sehrgross"; document.getElementById("kleiner_img").src = "image/all/minus.gif";			document.getElementById("groesser_img").src = "image/all/plus.gif"; }
	
	if (title == 'sehrgross') 					 { document.getElementById("verkleinern").title = "groesser"; 	document.getElementById("kleiner_img").src = "image/all/minus.gif"; 		document.getElementById("groesser_img").src = "image/all/plus_grau.gif"; }
	if (title == 'groesser') 					 { document.getElementById("verkleinern").title = "gross"; 		document.getElementById("kleiner_img").src = "image/all/minus.gif"; 		document.getElementById("groesser_img").src = "image/all/plus.gif"; }
	if (title == 'gross') 						 { document.getElementById("verkleinern").title = "normal"; 	document.getElementById("kleiner_img").src = "image/all/minus.gif"; 		document.getElementById("groesser_img").src = "image/all/plus.gif"; }
	
}

function setActiveStyleSheet(title) {
  var i, a, main;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
      a.disabled = true;
      if(a.getAttribute("title") == title) {
		  a.disabled = false;
		  getNextStyleSheet(title);  
	  }
    }
  }
  createCookie("style", title, 365);
}

function getActiveStyleSheet() {
  var i, a, x;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title") && !a.disabled) {
        x = a.getAttribute("title");
    }
  }
  return x;
}

function getPreferredStyleSheet() {
  var i, a;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1
       && a.getAttribute("rel").indexOf("alt") == -1
       && a.getAttribute("title")
       ) return a.getAttribute("title");
  }
  return null;
}

function createCookie(name,value,days) {
  if (days) {
    var date = new Date();
    date.setTime(date.getTime()+(days*24*60*60*1000));
    var expires = "; expires="+date.toGMTString();
  }
  else expires = "";
  document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
  var nameEQ = name + "=";
  var ca = document.cookie.split(';');
  for(var i=0;i < ca.length;i++) {
    var c = ca[i];
    while (c.charAt(0)==' ') c = c.substring(1,c.length);
    if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
  }
  return null;
}
/*
addEvent(window, "load", function(e) {
    var cookie = readCookie("style");
    var title = cookie ? cookie : getPreferredStyleSheet();
    setActiveStyleSheet(title);
});

addEvent(window, "unload", function(e) {
    var title = getActiveStyleSheet();
    createCookie("style", title, 365);
});
*/