.slowFade {
  display: flex;
  align-items: flex-start;
  background: #fff;
  height: 350px;
  overflow: hidden;
  position: relative;
}
.slowFade .slide img {
  position: absolute;
  min-width: 100%;
  min-height: 100%;
  height: 100%;
  background: #000;
  -webkit-backface-visibility: hidden;
          backface-visibility: hidden;
  opacity: 0;
 
  -webkit-animation: slowFade 12s infinite;
          animation: slowFade 12s infinite;
}

.slowFade .slide:nth-child(2) img {
  -webkit-animation-delay: 4s;
          animation-delay: 4s;
}
.slowFade .slide:nth-child(1) img {
  -webkit-animation-delay: 8s;
          animation-delay: 8s;
}
@keyframes slowFade {
  25% {
      opacity: 1;
    
  }
  40% {
      opacity: 0;
  }
}

@-webkit-keyframes slowFade {
  25% {
      opacity: 1;
    
  }
  40% {
      opacity: 0;
  }
}