<button type="button" class="icon">
  <div class="cloud">
    <div class="puff puff-1"></div>
    <div class="puff puff-2"></div>
    <div class="puff puff-3"></div>
    <div class="puff puff-4"></div>
    <div class="puff puff-5"></div>
    <div class="puff puff-6"></div>
    <div class="puff puff-7"></div>
    <div class="puff puff-8"></div>
    <div class="puff puff-9"></div>
    <div class="puff puff-10"></div>
    <div class="cloud-core"></div>
    <div class="check"></div>
    <div class="arrow">
      <div class="arrow-stem">
        <div class="arrow-l-tip"></div>
        <div class="arrow-r-tip"></div>
      </div>
    </div>
  </div>
  <div class="preload">
    <div class="drop drop-1"></div>
    <div class="drop drop-2"></div>
    <div class="drop drop-3"></div>
  </div>
  <div class="progress"></div>
</button>

*, *:before, *:after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}
body {
  background-color: #ace;
}
.icon {
  background-color: transparent;
  border: 0;
  color: #557eef;
  cursor: pointer;
  display: block;
  font-size: 20px;
  margin: 3em auto 0 auto;
  position: relative;
  width: 9em;
  height: 9em;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
}
.icon:focus {
  /* This may be anti-A11Y, but just for this demo suppresses the annoyance */
  outline: 0;
}
.icon div {
  position: absolute;
}
.cloud {
  transition: opacity 0.1s linear;
}
/* Cloud */
.cloud {
  top: 0;
  width: 9em;
  height: 5.8em;
}
.puff, .cloud-core {
  background-color: #fff;
}
.puff {
  border-radius: 50%;
}
.puff-1 {
  top: 2.5em;
  left: 0;
  width: 3.3em;
  height: 3.3em;
}
.puff-2 {
  top: 1em;
  left: 1.2em;
  width: 3em;
  height: 3em;
}
.puff-3 {
  top: 0;
  left: 3em;
  width: 4.6em;
  height: 4.6em;
}
.puff-4 {
  top: 1.8em;
  left: 5em;
  width: 4em;
  height: 4em;
}
.puff-5 {
  top: 2.3em;
  left: 2.4em;
  width: 3.5em;
  height: 3.5em;
}
.puff-6 {
  top: 2.3em;
  left: 3em;
  width: 3.5em;
  height: 3.5em;
}
.puff-7 {
  top: 2.4em;
  left: 1em;
  width: 1.8em;
  height: 1.8em;
}
.puff-8 {
  top: 1.2em;
  left: 2.5em;
  width: 2em;
  height: 2em;
}
.puff-9 {
  top: 1.8em;
  left: 5.5em;
  width: 2em;
  height: 2em;
}
.puff-10 {
  top: 3.6em;
  left: 3.5em;
  width: 2.2em;
  height: 2.2em;
}
.cloud-core {
  top: 1.8em;
  left: 1.8em;
  width: 5em;
  height: 4em;
}
.check {
  top: 0;
  left: 1.6em;
  width: 5.8em;
  height: 5.8em;
  position: relative;
  transform: scale(0);
  z-index: -1;
}
.check:before, .check:after {
  background-color: currentColor;
  content: "";
  bottom: 0;
  display: block;
  left: 2.5em;
  position: absolute;
  width: 0.8em;
}
.check:before {
  height: 3em;
  transform: rotate(-55deg);
  transform-origin: 50% 2.6em;
}
.check:after {
  height: 5.5em;
  transform: rotate(35deg);
  transform-origin: 50% 5.1em;
}
/* Arrow */
.arrow {
  top: 3em;
  left: 0;
  width: 9em;
  height: 5.3em;
}
.arrow div, .progress {
  border-radius: 0.4em;
}
.arrow div {
  background-color: currentColor;
}
.arrow-stem {
  bottom: 0;
  left: 4.1em;
  width: 0.8em;
  height: 5.3em;
  transform-origin: 50% 100%;
}
.arrow-l-tip, .arrow-r-tip {
  left: calc(50% - 0.4em);
  bottom: 0;
  width: 2.6em;
  height: 0.8em;
  transform-origin: 0.4em 50%;
}
.arrow-l-tip {
  transform: rotate(-135deg);
}
.arrow-r-tip {
  transform: rotate(-45deg);
}
.progress {
  background-color: #fff;
  bottom: 0;
  left: 0;
  width: 0;
  height: 0.8em;
}

/* Droplets */
.preload, .drop {
  transition: all 0.2s linear;
}
.preload {
  animation: spin 1s linear infinite;
  opacity: 0;
  top: 2.9em;
  left: calc(50% - 1.25em);
  width: 2.5em;
  height: 2.5em;
  z-index: 1;
}
.drop {
  background-color: currentColor;
  background-image: radial-gradient(0.5em 0.5em at 30% 75%,rgb(255,255,255) 45%, rgba(255,255,255,0) 50%);
  border-radius: 50%;
  width: 100%;
  height: 100%;
}
.drop-1 {
  transform: scaleY(0.75) rotate(135deg);
}
.drop-2 {
  transform: rotate(120deg) scaleY(0.75) rotate(135deg);
}
.drop-3 {
  transform: rotate(240deg) scaleY(0.75) rotate(135deg);
}

/** Animation **/
.waiting, .running {
  cursor: default;
}
/* Waiting */
.waiting .cloud {
  opacity: 0.15;
}
.waiting .preload {
  opacity: 1;
}
.waiting .drop {
  border-radius: 0 50% 50% 50%;
}
.waiting .drop-1 {
  transform: translateY(2.5em) scaleY(0.75) rotate(135deg);
}
.waiting .drop-2 {
  transform: rotate(120deg) translateY(2.5em) scaleY(0.75) rotate(135deg);
}
.waiting .drop-3 {
  transform: rotate(240deg) translateY(2.5em) scaleY(0.75) rotate(135deg);
}

/* Running */
.running .puff {
  animation-duration: 0.75s;
  animation-delay: 2.75s;
  animation-timing-function: cubic-bezier(.1,.8,.2,.95);
}
.running .puff-1 {
  animation-name: puff1;
}
.running .puff-2 {
  animation-name: puff2;
}
.running .puff-3 {
  animation-name: puff3;
}
.running .puff-4 {
  animation-name: puff4;
}
.running .puff-5 {
  animation-name: puff5;
}
.running .puff-6 {
  animation-name: puff6;
}
.running .puff-7 {
  animation-name: puff7;
}
.running .puff-8 {
  animation-name: puff8;
}
.running .puff-9 {
  animation-name: puff9;
}
.running .puff-10 {
  animation-name: puff10;
}
.running .cloud-core {
  animation: core 2.75s;
}
.running .check {
  animation: check 0.4s 2.75s;
}
.running .arrow {
  animation: arrow 0.125s;
}
.running .arrow-stem {
  animation: arrowStem 0.125s;
}
.running .arrow-l-tip {
  animation: arrowLTip 0.375s 0.125s;
}
.running .arrow-r-tip {
  animation: arrowRTip 0.375s 0.125s;
}
.running .progress {
  animation: filling 2s 0.75s;
}
.icon.running div {
  animation-fill-mode: forwards;
}
.icon.running .cloud-core, .icon.running .check, .icon.running .arrow, .icon.running .arrow div, .icon.running .progress {
  animation-timing-function: linear;
}

/* Keyframes */
@keyframes puff1 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(-4em,0) scale(0.1)}
}
@keyframes puff2 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(-2em,-2em) scale(0.1)}
}
@keyframes puff3 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(2em,-4em) scale(0.1)}
}
@keyframes puff4 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(4em,0) scale(0.1)}
}
@keyframes puff5 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(-3.5em,3.5em) scale(0.1)}
}
@keyframes puff6 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(3.5em,3.5em) scale(0.1)}
}
@keyframes puff7 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(-3em,-1.5em) scale(0.1)}
}
@keyframes puff8 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(-0.5em,-2em) scale(0.1)}
}
@keyframes puff9 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(2em,-2em) scale(0.1)}
}
@keyframes puff10 {
  from {opacity: 1;transform: translate(0) scale(1)}
  to {opacity: 0;transform: translate(0em,2.5em) scale(0.1)}
}
@keyframes core {
  from {visibility: visible}
  to {visibility: hidden}
}
@keyframes check {
  from {transform: scale(0)}
  30% {transform: scale(1.2)}
  60% {transform: scale(0.9)}
  to {transform: scale(1)}
}
@keyframes arrow {
  from {transform: translateY(0)}
  to {transform: translateY(0.7em)}
}
@keyframes arrowStem {
  from {height: 5.3em}
  to {height: 0.8em}
}
@keyframes arrowLTip {
  from {transform: rotate(-135deg)}
  50% {width: 2.6em;transform: rotate(-180deg)}
  to {width: 4.9em;transform: rotate(-180deg)}
}
@keyframes arrowRTip {
  from {transform: rotate(-45deg);}
  50% {width: 2.6em;transform: rotate(0deg)}
  to {width: 4.9em;transform: rotate(0deg)}
}
@keyframes filling {
  from {width: 0;}
  to {width: 100%;}
}
@keyframes spin {
  from {transform: rotate(0deg)}
  to {transform: rotate(1turn)}
}

document.addEventListener("DOMContentLoaded",function(){
  this.querySelector(".icon").addEventListener("click",function(){
    let waitClass = "waiting",
      runClass = "running",
      cl = this.classList;

    if (!cl.contains(waitClass) && !cl.contains(runClass)) {
      cl.add(waitClass);
      setTimeout(function(){
        cl.remove(waitClass);
        setTimeout(function(){
          cl.add(runClass);
          setTimeout(function(){
            cl.remove(runClass);
          }, 4000);
        }, 200);
      }, 1800);
    }
  });
});