Slideshow with Spinning Transition

HTML

<body>
  <div class="container">
    <div class="cover"></div>
    <div class="slide">
      <img src="https://picsum.photos/id/1011/5472/3648"/>
    </div>
    <div class="slide">
      <img src="https://picsum.photos/id/1035/5854/3903"/>
    </div>
    <div class="slide">
      <img src="https://picsum.photos/id/1074/5472/3648"/>
    </div>
    <div class="slide">
      <img src="https://picsum.photos/id/177/2515/1830"/>
    </div>
  </div>
</body>

CSS

body {
  height: 100vh;
  margin: 0;
}

.container {
  position: absolute;
  height: 100%;
  width: 100%;
}

.cover {
  position: absolute;
  height: 150vmax;
  width: 150vmax;
  left: calc(50% - 75vmax);
  top: calc(50% - 75vmax);
  pointer-events: none;
  z-index: 2;
  animation: rotateCover 10s linear infinite;
}

@keyframes  rotateCover {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(180deg);
  }
}

.cover:before, .cover:after {
  content: '';
  position: absolute;
  height: 100%;
  width: 100%;
  left: 50%;
  background-color: #2e3537;
  transform: translate3d(-50%, 0, 0);
  pointer-events: auto;
}

.cover:before {
  bottom: 50%;
  animation: slideTopCover 5s infinite;
}

@keyframes  slideTopCover {
  0% {
    transform: translate3d(-50%, 0, 0);
    animation-timing-function: cubic-bezier(0.8, 0, 0.1, 1);
  }
  40% {
    transform: translate3d(-50%, -65vmax, 0);
  }
  70% {
    transform: translate3d(-50%, -65vmax, 0);
  }
  100% {
    transform: translate3d(-50%, 0, 0);
    animation-timing-function: cubic-bezier(0.6, 0.04, 0.98, 0.335);
  }
}

.cover:after {
  top: 50%;
  animation: slideBottomCover 5s infinite;
}

@keyframes  slideBottomCover {
  0% {
    transform: translate3d(-50%, 0, 0);
    animation-timing-function: cubic-bezier(0.8, 0, 0.1, 1);
  }
  40% {
    transform: translate3d(-50%, 65vmax, 0);
  }
  70% {
    transform: translate3d(-50%, 65vmax, 0);
  }
  100% {
    transform: translate3d(-50%, 0, 0);
    animation-timing-function: cubic-bezier(0.6, 0.04, 0.98, 0.335);
  }
}

.slide {
  background-color: #2e3537;
  position: absolute;
  height: 100%;
  width: 100%;
  opacity: 0;
  animation: showHideSlide infinite 20s steps(1);
}

@keyframes  showHideSlide {
  0% {
    opacity: 1;
    pointer-events: auto;
    z-index: 1;
  }
  25% {
    opacity: 0;
    pointer-events: none;
    z-index: -1;
  }
  100% {
    opacity: 0;
    pointer-events: none;
    z-index: -1;
  }
}

.slide:nth-child(1) {
  animation-delay: 0s;
}

.slide:nth-child(2) {
  animation-delay: 5s;
}

.slide:nth-child(3) {
  animation-delay: 10s;
}

.slide:nth-child(4) {
  animation-delay: 15s;
}

.slide img {
  position: relative;
  height: 100%;
  width: 100%;
  object-fit: cover;
  opacity: 1;
  z-index: -1;
  animation: animate 5s infinite;
}

@keyframes  animate {
  0% {
    transform: rotate(-45deg) scale(1.1);
    animation-timing-function: cubic-bezier(0.165, 0.84, 0.44, 1);
  }
  33% {
    transform: rotate(0deg);
  }
  50% {
    transform: rotate(0deg);
  }
  66% {
    transform: rotate(0deg);
    animation-timing-function: cubic-bezier(0.895, 0.03, 0.685, 0.22);
  }
  100% {
    transform: rotate(45deg) scale(0.9);
  }
}