.slideshow {
  background: #000;
}
.slideshow, .slideshow .slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}
.slideshow .slide {
  background-position: center;
  background-size: cover;
  opacity: 0;
}
.slideshow .slide.previous {
  z-index: 1;
  opacity: 1;
}
.slideshow .slide.current {
  z-index: 2;
  -webkit-animation: fadein 5000ms linear both;
          animation: fadein 5000ms linear both;
}

@-webkit-keyframes fadein {
  0% {
    opacity: 0;
  }
  30% {
    opacity: 1;
  }
  100% {
    opacity: 1;
  }
}

@keyframes fadein {
  0% {
    opacity: 0;
  }
  30% {
    opacity: 1;
  }
  100% {
    opacity: 1;
  }
}