#slider {
  position: relative;
}

#slider img {
  height: 240px;
  width: auto;
}

.slider {
  position: relative;
}
.slider__item {
  display: flex;
  justify-content: center;
  align-items: center;
  color: transparent;
  position: absolute;
  top: 0;
  z-index: 0;
  opacity: 0;
  transition: all 1s ease;
}
.showing {
  opacity: 1;
  z-index: 1;
  /* image-rendering: -webkit-optimize-contrast; */
}