.scrollbarRail {
  position: absolute;
  right: 0;
  height: 80%;
  width: 0.6em;
  margin-right: 0.4em;
  background-color: transparent;
  transition: background-color 0.1s;
}

.scrollbar {
  position: relative;
  width: inherit;
  background-color: #D0D0D0;
  border: 1px solid grey;
  opacity: 0.5;
}

.scrollbarRail:hover { background-color: #E8E8E8; }
.scrollbarRail:hover .scrollbar { opacity: 1; }