.Navigation-back {
  z-index: 3 !important; // z-index of an active .btn-group .btn is 2
  border-radius: @border-radius !important;
  .transition(border-radius 0.2s);
}
.Navigation-pin {
  opacity: 0;
  margin-left: -5px !important;
  border-radius: 0 @border-radius @border-radius 0;
  .transition(~"opacity 0.2s, margin-left 0.2s");

  .icon {
    .rotate(45deg);
  }
}

@media @desktop-hd {
  .hasPane.panePinned, .hasPane.paneShowing {
    .Navigation-back {
      border-radius: @border-radius 0 0 @border-radius !important;
    }
    .Navigation-pin {
      opacity: 1;
      margin-left: 1px !important;
    }
  }
  .hasPane.panePinned .Navigation-pin .icon {
    .rotate(0deg);
  }
}