function dotclosed(id)
 { return document.getElementById('dots_' + id).firstChild.firstChild.className == 'openimg'
 }
function dotclose(id) { dotstate(id, 'down', 'openimg') }
function dotopen(id) { dotstate(id, 'up', 'closeimg') }
function dotstate(id, src, cn)
 { var img; img = document.getElementById('dots_' + id).firstChild.firstChild;
   img.className = cn; img.src = '/images/' + src + '.gif'
 }
var vantag = document.createTextNode(String.fromCharCode(160)); //it is  
function vantaggino()
 { var div, empty;
   div = document.getElementById('vantaggino'); empty = !div.hasChildNodes();
   if(!empty) div.removeChild(div.firstChild); else div.appendChild(vantag)
 }