message: Rotate historyBack and historyForward buttons.
diff: width: 128px;
  }
  +#historyBack {
  + transform: rotate(-90deg);
  +}
  +
  +#historyForward {
  + transform: rotate(-90deg);
  +}
  +
  .pdfViewer.removePageBorders .page {
  border: none;
  box-shadow: 0px 0px 0px 1px lightgrey;
  