table.js-sortable th {
  cursor: pointer;
  position: relative;
  padding-right: 20px;
}

table.js-sortable th.sorted-asc,
table.js-sortable th.sorted-desc {
  color: rebeccapurple;
}

table.js-sortable th.sorted-asc::after,
table.js-sortable th.sorted-desc::after {
  content: '';
  position: absolute;
  right: 0;
  width: 0;
  height: 0;
  top: 3px;
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
}

table.js-sortable th.sorted-asc::after {
  border-top: 8px solid rebeccapurple;
}

table.js-sortable th.sorted-desc::after {
  border-bottom: 8px solid rebeccapurple;
}