<!--  
https://tympanus.net/codrops/2013/05/22/examples-of-pseudo-elements-animations-and-transitions/
-->
<div class="main">
  <div class="drop"></div>
</div>

@import url("https://fonts.googleapis.com/css2?family=Exo:wght@600&display=swap");

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  width: 100vw;
  min-height: 100vh;
  font-family: "Exo", Arial, sans-serif;
  background-color: #557;
  padding: 20px;

  display: grid;
  place-content: center;
}

.drop {
  background: rgba(255, 255, 245, 1);
  border: 4px solid rgba(255, 245, 235, 1);
  border-radius: 100%;
  box-shadow: inset -0.1em 0 2em 0.5em rgba(255, 255, 255, 0.5),
    inset -0.1em 0 0.5em 0 rgba(0, 0, 0, 0.8);
  position: relative;
  margin: 0 auto;
  width: 15em;
  height: 15em;
  overflow: hidden;
  transform-style: preserve-3d;
}

.drop::before,
.drop::after {
  content: "";
  display: block;
  position: absolute;
}

.drop::before {
  background: rgba(167, 217, 234, 1);
  border-radius: 100%;
  box-shadow: 0 0 0 0.1em rgba(167, 217, 234, 0.8),
    0 0 0 0.15em rgba(167, 217, 234, 0.8), 0 0 0 0.2em rgba(167, 227, 234, 0.8),
    0 0 0 0.25em rgba(167, 227, 234, 0.8), 0 0 0 0.3em rgba(167, 227, 234, 0.8),
    0 0 0 0.35em rgba(167, 227, 234, 0.8), 0 0 0 0.4em rgba(167, 227, 234, 0.8),
    0 0 0 0.45em rgba(167, 227, 234, 0.8), 0 0 0 0.5em rgba(167, 227, 234, 0.8);
  top: 0%;
  left: 50%;
  width: 0.2em;
  height: 0.2em;

  animation: fall 3.5s cubic-bezier(0.5, 0, 1, 0.5) infinite;
}

.drop::after {
  background: rgb(52, 152, 219);
  background: linear-gradient(
    rgba(52, 255, 255, 1) 0%,
    rgba(52, 152, 219, 1) 10%,
    rgba(152, 252, 219, 1) 100%
  );
  border-radius: 100% 0 50% 0;
  left: 0;
  bottom: 0;
  width: inherit;
  height: 3em;
  opacity: 0.7;
  animation: surface 3s linear infinite;
}

@keyframes fall {
  5%,
  15% {
    box-shadow: 0 -1.4em 0 0.1em rgba(167, 217, 234, 1),
      0 -0.8em 0 0.15em rgba(167, 217, 234, 1),
      0 -0.3em 0 0.2em rgba(167, 217, 234, 1),
      0 -0.1em 0 0.25em rgba(167, 217, 234, 1),
      0 0 0 0.3em rgba(167, 217, 234, 1),
      0 0.2em 0 0.35em rgba(167, 217, 234, 1),
      0 0.4em 0 0.4em rgba(167, 217, 234, 1),
      0 0.6em 0 0.45em rgba(167, 217, 234, 1),
      0 0.8em 0 0.5em rgba(167, 217, 234, 1);
  }
  16% {
    top: 80%;
  }
  18% {
    top: 80%;
    box-shadow: 1em -8em 0 0.2em rgba(177, 227, 234, 1),
      -2.2em -3.8em 0 0.1em rgba(177, 227, 234, 1),
      3em -2.85em 0 0.3em rgba(177, 227, 234, 1),
      -3.5em -4em 0 0.2em rgba(177, 227, 234, 1),
      0 0 0 0.3em rgba(177, 227, 234, 1),
      2em -2em 0 0.2em rgba(177, 227, 234, 1),
      -0.3em -3em 0 0.2em rgba(177, 227, 234, 1),
      0.5em -5em 0 0.35em rgba(177, 227, 234, 1),
      -3em -1em 0 0.3em rgba(177, 227, 234, 1);
  }
  30% {
    top: 90%;
    box-shadow: 1.5em 0 0 0.2em rgba(252, 252, 255, 0.1),
      -2em 0 0 0.15em rgba(252, 252, 255, 0.1),
      3em 0 0 0.2em rgba(252, 252, 255, 0.1),
      -2em 0 0 0.25em rgba(252, 252, 255, 0.1),
      0 0 0 0.2em rgba(252, 252, 255, 0.1),
      2.35em 0 0 0.3em rgba(252, 252, 255, 0.1),
      -0.5em 0 0 0.2em rgba(252, 252, 255, 0.1),
      1em 0 0 0.3em rgba(252, 252, 255, 0.1),
      -4em 0 0 0.4em rgba(252, 252, 255, 0.1);
  }
  40%,
  100% {
    top: 95%;
    background: rgba(255, 255, 255, 1);
    box-shadow: 1.8em 0.5em 0 0.2em rgba(255, 255, 255, 0),
      -3em 0.5em 0 0.1em rgba(255, 255, 255, 0),
      4em 0.5em 0 0.1em rgba(255, 255, 255, 0),
      -3.5em 0.5em 0 0.1em rgba(255, 255, 255, 0),
      0 0 0 0.3em rgba(255, 255, 215, 0),
      2.45em 0.5em 0 0.1em rgba(255, 255, 255, 0),
      -0.8em 0.5em 0 0.2em rgba(255, 255, 255, 0),
      1.5em 0.5em 0 0.3em rgba(255, 255, 255, 0),
      -4.5em 0.5em 0 0.2em rgba(255, 255, 255, 0);
  }
}

@keyframes surface {
  50% {
    border-radius: 0 75% 0 75%;
    opacity: 0.5;
    height: 3.5em;
  }
}