<div class="sky">
  <div class="sun-object">
    <div class="sun ray rotated"></div>
    <div class="sun ray squared"></div>
    <div class="sun orb glow"></div>
    <div class="sun orb"></div>
  </div>
  <div class="cloud alpha"></div>
  <div class="cloud beta"></div>
  <div class="cloud charlie"></div>
</div>
.alpha {
  animation-duration: 10s;
  box-shadow: -0.1em 0.1em 2.5em 0.1em #999;
  left: 50%;
  top: 50%;
}
.beta {
  animation-duration: 15s;
  height: 5%;
  left: 20%;
  opacity: 0.7;
  top: 20%;
  width: 15%;
}
.charlie {
  animation-duration: 20s;
  height: 3%;
  left: 50%;
  opacity: 0.4;
  top: 10%;
  width: 9%;
}
.cloud {
  animation-iteration-count: infinite;
  animation-name: fluffy;
  animation-timing-function: cubic-bezier(0.1, 0.7, 0.5, 0.1);
  border-radius: 20% 70% 5% 5% / 55% 70% 25% 35%;
  height: 5vmin;
  width: 15vmin;
}
.cloud,
.cloud:before,
.cloud:after {
  background-color: #fff;
  position: absolute;
}
.cloud:after {
  height: 125%;
  left: 50%;
  top: -50%;
  width: 40%;
}
.cloud:before {
  height: 175%;
  left: 15%;
  top: -85%;
  width: 50%;
}
.cloud:before,
.cloud:after {
  border-radius: 50%;
  content: "";
}
.glow {
  animation-duration: 3s;
  animation-iteration-count: infinite;
  animation-name: shine;
  animation-timing-function: ease-in-out;
  box-shadow: 0 0 30vmin 0 #fae452;
}
.orb {
  background-image: -webkit-linear-gradient(
    top left,
    #fae65c 50%,
    #fae452 100%
  );
  background-image: linear-gradient(to bottom right, #fae65c 50%, #fae452 100%);
  border-radius: 50%;
  transition: box-shadow 1s ease-in-out;
}
.ray {
  background-color: #f9e294;
}
.rotated {
  background-image: -webkit-linear-gradient(left, #e7b439 25%, #7c612b 100%);
  background-image: linear-gradient(to right, #e7b439 25%, #7c612b 100%);
  transform: rotate(45deg);
}
.sky {
  background: #7baaf7;
  border: 1vmin solid #639bf6;
  border-bottom: none;
  border-radius: 50%;
  height: 95vmin;
  left: 50%;
  overflow: hidden;
  position: absolute;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 95vmin;
}
.squared {
  background-image: -webkit-linear-gradient(
    top left,
    #f9e294 25%,
    #7c612b 100%
  );
  background-image: linear-gradient(to bottom right, #f9e294 25%, #7c612b 100%);
}
.sun {
  background-color: #fae65c;
  height: 100%;
  left: 0;
  position: absolute;
  top: 0;
  width: 100%;
}
.sun-object {
  height: 33%;
  left: 33%;
  position: relative;
  top: 33%;
  width: 33%;
  border: 1px solid gray;
}
body {
  background-color: #f2f2f2;
  transition: background-color ease-in-out 1s;
}
@media only screen and (max-width: 500px) {
  .sky {
    border: none;
    overflow: visible;
  }
  ::-webkit-scrollbar {
    display: none;
  }
  body {
    background-color: #7baaf7;
  }
}
@-webkit-keyframes shine {
  0%,
  100% {
    opacity: 0;
  }
  50% {
    opacity: 1;
  }
}
@keyframes shine {
  0%,
  100% {
    opacity: 0;
  }
  50% {
    opacity: 1;
  }
}
@-webkit-keyframes fluffy {
  from {
    transform: translateX(-100vw);
  }
  to {
    transform: translateX(100vw);
  }
}
@keyframes fluffy {
  from {
    transform: translateX(-100vw);
  }
  to {
    transform: translateX(100vw);
  }
}
// taken from Inbox by Google
// i.e., the image used for empty inbox
// re-done using CSS animations + resizes based relative viewport

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