Rubenz smooth scroll bar

[data-scrollbar] {
  display: block;
  position: relative;
}

.scroll-content {
  -webkit-transform: translate3d(0, 0, 0);
  transform: translate3d(0, 0, 0);
}

.scrollbar-track {
  position: absolute;
  opacity: 0;
  z-index: 1;
  background: rgba(222, 222, 222, .75);
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
  -webkit-transition: opacity 0.5s 0.5s ease-out;
  transition: opacity 0.5s 0.5s ease-out;
}

.scrollbar-track.show,
.scrollbar-track:hover {
  opacity: 1;
  -webkit-transition-delay: 0s;
  transition-delay: 0s;
}

.scrollbar-track-x {
  bottom: 0;
  left: 0;
  width: 100%;
  height: 8px;
}

.scrollbar-track-y {
  top: 0;
  right: 0;
  width: 8px;
  height: 100%;
}

.scrollbar-thumb {
  position: absolute;
  top: 0;
  left: 0;
  width: 8px;
  height: 8px;
  background: rgba(0, 0, 0, .5);
  border-radius: 4px;
}