table.sortable span.arrow {
  border-style: solid;
  border-width: 5px;
  display: block;
  position: absolute;
  top: 50%;
  right: 5px;
  font-size: 0;
  border-color: #ccc transparent transparent transparent;
  line-height: 0;
  height: 0;
  width: 0;
  margin-top: -2px;
}

table.sortable span.arrow.up {
  border-color: transparent transparent #ccc transparent;
  margin-top: -7px;
}

table.sortable thead th {
  cursor: pointer;
  position: relative;
  top: 0;
  left: 0;
}

table.sortable thead th:hover:not([data-defaultsort=disabled]) {
  background: #efefef;
}

table.sortable thead th div.mozilla {
  position: relative;
}