.slide {
  width: 750px;
  height: 500px;
  display: flex;
  justify-content: center;
  align-items: center;
  position: absolute;
  top: 0;
  transform: scale(0.99);
  opacity: 0.0;
  transition: all 3.5s ease-in-out;
}
.showing {
  z-index: 1;
  transform: none;
  opacity: 1;
}