docs: function(elem, id) {
              if (typeof elem === 'string') {
                  elem = document.getElementById(elem);
                  if (!elem) return null;
              }
              var copy = elem.cloneNode(true);
              if (typeof id === 'string') {
                  var i, div, divs, prefix = id + ".";
                  divs = copy.querySelectorAll("[id]");
                  for (i = 0 ; i < divs.length ; i++) {
                      div = divs[i];
                      div.setAttribute("id", prefix + div.getAttribute("id"));
                  }
                  delete copy.style.display;
                  copy.removeAttribute("style");
                  copy.setAttribute("id", id);
              }
              return copy;
          }