.viewport {
  position: relative;
  overflow: hidden;
  /* Force the scrollbar into LTR mode so it is reliably aligned to the left. */
  direction: ltr;
}

/* scrollable is in LTR mode even if the body is in RTL mode. */
@noflip {
  .scrollable {
    position: absolute;
    top: 0;
    right: 0;
    height: 100%;
    width: 100px;
    overflow-y: scroll;
    overflow-x: hidden;
  }
}