// JavaScript Document Guide
function openArticle(idArt) {
  idBloc = idArt.substr(0, (idArt.length-1));
  if (!eval(document.getElementById(idArt+"b"))) return;
  for(i=1; document.getElementById(idBloc+i+"b") || document.getElementById(idBloc+(i+1)+"b"); i++)
  {
    itemA = eval(document.getElementById(idBloc+i+"a"));
    itemB = eval(document.getElementById(idBloc+i+"b"));
    if(idBloc+i!=idArt) {
      if(itemA.className.substr((itemA.className.length-3), 3)=="_on") itemA.className = itemA.className.substr(0, (itemA.className.length-3));
      if(itemB) itemB.style.display = 'none';
    }
    else {
      if(itemA.className.substr((itemA.className.length-3), 3)!="_on") itemA.className = itemA.className+"_on";
      if(itemB) itemB.style.display = 'block';
    }
  }
}