Weather icon animation effect implemented by CSS3

<div class="wrapper">
  <div class="sun"></div>
  <div class="cloud">
    <div class="cloud1">
      <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
    <div class="cloud1 c_shadow">
      <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
  </div>
  
  <div class="cloud_s">
    <div class="cloud1">
      <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
    <div class="cloud1 c_shadow">
      <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
  </div>
  
  <div class="cloud_vs">
    <div class="cloud1">
      <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
    <div class="cloud1 c_shadow">
      <ul>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
  </div>
  <div class="haze"></div>
  <div class="haze_stripe"></div>
  <div class="haze_stripe"></div>
  <div class="haze_stripe"></div>
  <div class="thunder"></div>
  <div class="rain">
     <ul>
       <li></li>
       <li></li>
       <li></li>
    </ul>
  </div>
  <div class="sleet">
     <ul>
       <li></li>
       <li></li>
       <li></li>
    </ul>
  </div>
  <div class="text">
    <ul>
      <li>Mostly Sunny</li>
      <li>Partly Sunny</li>
      <li>Partly Cloudy</li>
      <li>Mostly Cloudy</li>
      <li>Cloudy</li>
      <li>Hazy</li>
      <li>Thunderstorm</li>
      <li>Rain</li>
      <li>Sleet</li>
    </ul>
  </div>
</div>

@import url(https://fonts.googleapis.com/css?family=Raleway+Dots);

body{
  margin: 0;
  padding: 0;
  background: #33495f;
}

.wrapper{
  width: 150px;
  height: 150px;
  position: absolute;
  top: calc(50% - 75px);
  left: calc(50% - 75px);
}

.sun{
  position: absolute;
  bottom: 0px;
  right: 0px;
  width: 85px;
  height: 85px;
  background: #f9db62;
  border-radius: 360px;
  opacity: 1;
  animation: sun 10s 0s linear infinite;
}

.cloud{
  position: absolute;
  bottom: 12px;
  left: 8px;
  z-index: 2;
  opacity: 0;
  animation: cloud 10s 0s linear infinite;
}

.cloud .cloud1:not(.c_shadow) ul li{
  animation: cloudi 10s 0.1s linear infinite;
}

.cloud .cloud1:not(.c_shadow):before{
  animation: cloudi 10s 0s linear infinite;
}

.cloud_s{
  position: absolute;
  bottom: 70px;
  left: 150px;
  transform: scale(0.7,0.7) matrix(-1, 0, 0, 1, 0, 0);
  z-index: 1;
  opacity: 0;
  animation: cloud_s 10s 0s linear infinite;
}

.cloud_s .c_shadow{
  transform: scale(1.02,1.02);
}

.cloud_vs{
  position: absolute;
  bottom: 90px;
  left: 30px;
  transform: scale(0.5,0.5);
  z-index: 0;
  opacity: 0;
  animation: cloud_vs 10s 0s linear infinite;
}

.c_shadow{
  z-index: 4 !important;
  left: -5px;
  bottom: -3px !important;
}

.c_shadow:before{
  background: #33495f !important;
}

.c_shadow ul li{
  width: 60px !important;
  height: 60px !important;
  background: #33495f !important;
  float: left;
  position: absolute;
  bottom: -2px !important;
  border-radius: 360px;
}

.c_shadow ul li:nth-child(2){
  width: 80px !important;
  height: 80px !important;
  background: #33495f !important;
  float: left;
  border-radius: 360px;
  position: absolute;
  bottom: 16px !important;
  left: 25px !important;
}

.c_shadow ul li:nth-child(3){
  width: 70px !important;
  height: 70px !important;
  background: #33495f !important;
  float: left;
  border-radius: 360px;
  position: absolute;
  bottom: 6px !important;
  left: 60px !important;
}

.c_shadow ul li:last-child{
  width: 60px !important;
  height: 60px !important;
  background: #33495f !important;
  float: left;
  border-radius: 360px;
  position: absolute;
  bottom: 0px;
  left: 90px;
}


.cloud1{
  position: absolute;
  bottom: 0px;
  z-index: 5;
}

.cloud1:before{
  content: '';
  position: absolute;
  bottom: 0px;
  left: 28px;
  width: 90px;
  height: 20px;
  background: #fff;
}

.cloud1 ul{
  list-style: none;
  margin: 0;
  padding: 0;
}

.cloud1 ul li{
  width: 50px;
  height: 50px;
  background: #fff;
  float: left;
  border-radius: 360px;
}

.cloud1 ul li:nth-child(2){
  width: 70px;
  height: 70px;
  background: #fff;
  float: left;
  border-radius: 360px;
  position: absolute;
  bottom: 18px;
  left: 25px;
}

.cloud1 ul li:nth-child(3){
  width: 60px;
  height: 60px;
  background: #fff;
  float: left;
  border-radius: 360px;
  position: absolute;
  bottom: 8px;
  left: 60px;
}

.cloud1 ul li:last-child{
  width: 50px;
  height: 50px;
  background: #fff;
  float: left;
  border-radius: 360px;
  position: absolute;
  bottom: 0px;
  left: 90px;
}

.haze{
  background: #33495f;
  position: absolute;
  bottom: 50px;
  left: 0px;
  width: 200px;
  height: 45px;
  z-index: 6;
  opacity: 0;
  animation: haze 10s 0s linear infinite;
}

.haze_stripe{
  background: #a3b5c7;
  position: absolute;
  bottom: 75px;
  left: 20px;
  width: 115px;
  height: 10px;
  z-index: 17;
  opacity: 0;
  border-radius: 360px;
  animation: haze_stripe 10s 0.1s linear infinite;
}

.haze_stripe:nth-child(6){
  bottom: 55px;
  animation: haze_stripe 10s 0.2s linear infinite;
}
.haze_stripe:last-child{
  bottom: 35px;
  animation: haze_stripe 10s 0.4s linear infinite;
}

.thunder{
  position: absolute;
  bottom: 100px;
  left: 65px;
  width: 12px;
  height: 12px;
  background: #f9db62;
  transform: skew(-25deg);
  opacity: 0;
  animation: thunder 10s 0s linear infinite;
}

.thunder:before{
  content: '';
  position: absolute;
  top: 11px;
  left: 0px;
  width: 25px;
  height: 8px;
  background: #f9db62;
}

.thunder:after{
  content: '';
  position: absolute;
  width: 0; 
  height: 0;
  top: 18px;
  right: -14px;
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  
  border-top: 20px solid #f9db62;
  transform: skew(5deg);
}

.rain{
  position: absolute;
  bottom: 0px;
  left: 25px;
}

.rain ul{
  list-style: none;
  margin: 0;
  padding: 0px;
}

.rain ul li{
  float: left;
  position: absolute;
  bottom: 50px;
  left: 50px;
  margin-left: 20px;
  background: #6ab9e9;
  height: 40px;
  width: 10px;
  border-radius: 360px;
  transform: rotate(35deg);
  opacity: 0;
}

.rain ul li:first-child{
  animation: raini 10s 0s linear infinite;
}

.rain ul li:nth-child(2){
  animation: rainii 10s 0.2s linear infinite;
}

.rain ul li:last-child{
  animation: rainiii 10s 0.4s linear infinite;
}

.sleet{
  position: absolute;
  bottom: 0px;
  left: 25px;
}

.sleet ul{
  list-style: none;
  margin: 0;
  padding: 0px;
}

.sleet ul li{
  float: left;
  position: absolute;
  bottom: 50px;
  left: 50px;
  margin-left: 20px;
  background: #fff;
  height: 40px;
  width: 10px;
  border-radius: 360px;
  transform: rotate(35deg);
  opacity: 0;
}

.sleet ul li:first-child{
  animation: raini 10s 1.0s linear infinite;
}

.sleet ul li:nth-child(2){
  animation: rainii 10s 1.4s linear infinite;
}

.sleet ul li:last-child{
  animation: rainiii 10s 1.6s linear infinite;
}

.text{
  position: absolute;
  bottom: 0px;
}

.text ul{
  list-style: none;
  margin: 0;
  padding: 0;
}

.text ul li{
  position: absolute;
  bottom: -50px;
  width: 150px;
  color: #fff;
  font-family: 'Raleway Dots', cursive;
  font-weight: 100;
  font-size: 20px;
  text-align: center;
  opacity: 0;
}

.text ul li:first-child{
  animation: fade_in 10.0s 0s linear infinite;
}

.text ul li:nth-child(2){
  animation: fade_in 10.0s 1.6s linear infinite;
}

.text ul li:nth-child(3){
  animation: fade_in 10.0s 2.4s linear infinite;
}

.text ul li:nth-child(4){
  animation: fade_in 10.0s 3.4s linear infinite;
}

.text ul li:nth-child(5){
  animation: fade_in 10.0s 4.0s linear infinite;
}

.text ul li:nth-child(6){
  animation: fade_in 10.0s 5.4s linear infinite;
}

.text ul li:nth-child(7){
  animation: fade_in 10.0s 6.4s linear infinite;
}

.text ul li:nth-child(8){
  animation: fade_in 10.0s 7.2s linear infinite;
}

.text ul li:nth-child(9){
  animation: fade_in 10.0s 8.2s linear infinite;
}

@keyframes sun{
  0%{
    opacity: 1;
    bottom: 35px;
    right: 35px;
  }
  4%
    bottom: 80px;
    right: 80px;
  }
  4.5%
    bottom: 75px;
    right: 75px;
    opacity: 1;
  }
  40%
    opacity: 1;
  }
  41%
    bottom: 75px;
    right: 75px;
    opacity: 0;
  }
  100%{
    opacity: 0;
    bottom: 0px;
    right: 0px;
  }
}

@keyframes cloud{
  0%{
    transform: scale(0.8);
    left: 120px;
    bottom: 35px;
    opacity: 0;
  }
  2%{
    opacity: 1;
  }
  3.5%
    bottom: 35px;
    left: 10px;
    opacity: 1;
  }
  16%
    transform: scale(0.8);
  }
  18%
    transform: scale(0.95);
  }
  19%
    transform: scale(0.9);
  }
  48%
    opacity: 1;
    bottom: 35px;
  }
  50%{
    bottom: 70px;
  }
  64%
    
  }
  96%
    opacity: 1;
  }
  100%{
    opacity: 0;
    bottom: 70px;
    left: 10px;
  }
}

@keyframes cloud_s{
  0%{
    transform: scale(0.6);
    opacity: 0;
    bottom: 40px;
    left: 18px;
  }
  twenty three%{
    opacity: 0;
  }
  twenty four%{
    opacity: 1;
    bottom: 40px;
    left: 30px;
  }
  28%
    opacity: 1;
    bottom: 85px;
    left: 60px;
  }
  32%
    transform: scale(0.6);
  }
  34%
    transform: scale(0.75);
  }
  35%
    transform: scale(0.7);
  }
  48%
    opacity: 1;
  }
  49%
    opacity: 0;
  }
  100%{
    transform: scale(0.7);
    opacity: 0;
    bottom: 85px;
    left: 60px;
  }
}

@keyframes cloud_vs{
  0%{
    opacity: 0;
    bottom: 85px;
    left: 60px;
  }
  39%
    opacity: 0;
  }
  40%
    opacity: 1; 
    bottom: 85px;
    left: 60px;
  }
  42%
    bottom: 125px;
    left: 10px;
  }
  43%
    bottom: 120px;
    left: 15px;
  }
  48%
    opacity: 1;
  }
  49%
    opacity: 0;
  }
  100%{
    opacity: 0;
    bottom: 120px;
    left: 15px;
  }
}

@keyframes haze{
  0%{
    opacity: 0;
  }
  48%
    height: 0px;
    opacity: 0;
  }
  49%
    height: 45px;
    opacity: 1;
  }
  57%
    opacity:1;
    height: 45px;
  }
  58%
    opacity: 0;
    height: 0px;
  }
}

@keyframes haze_stripe{
  0%{
    opacity: 0;
  }
  48%
    opacity: 0;
  }
  49%
    opacity: 1;
  }
  56%
    opacity:1;
  }
  57%
    opacity: 0;
  }
}

@keyframes cloudi{
  0%{
    background: #fff;
  }
  56%
    background: #fff;
  }
  57%
    background: #92a4b6;
  }
  100%{
    background: #92a4b6;
  }
}

@keyframes thunder{
  0%{
    opacity: 0;
    bottom: 100px;
    left: 65px;
  }
  62%
    opacity: 0;
    bottom: 100px;
    left: 65px;
  }
  64%
    opacity: 1;
    bottom: 50px;
    left: 60px;
  }
  65%
    opacity: 1;
    bottom: 55px;
    left: 61px;
  }
  72%
    opacity: 1;
    bottom: 55px;
    left: 61px;
  }
  73%
    opacity: 0;
  }
  100%{
    opacity: 0;
    bottom: 55px;
  }
}

@keyframes raini{
  0%{
    opacity: 0;
    bottom: 100px;
    left: 60px;
  }
  72%
    opacity: 0;
    bottom: 100px;
    left: 60px;
  }
  73%
    opacity: 1;
    bottom: 15px;
    left: 50px;
  }
  74%
    opacity: 1;
    bottom: 25px;
    left: 52px;
  }
  80%
    opacity: 1;
    bottom: 25px;
    left: 52px;
  }
  81%
    opacity: 0;
    bottom: -15px;
    left: 6px;
  }
  100%{
    opacity: 0;
    bottom: 20px;
  }
}

@keyframes rainii{
  0%{
    opacity: 0;
    bottom: 100px;
    left: 30px;
  }
  72%
    opacity: 0;
    bottom: 100px;
    left: 30px;
  }
  73%
    opacity: 1;
    bottom: 15px;
    left: 20px;
  }
  74%
    opacity: 1;
    bottom: 25px;
    left: 22px;
  }
  80%
    opacity: 1;
    bottom: 25px;
    left: 22px;
  }
  81%
    opacity: 0;
    bottom: -15px;
    left: -6px;
  }
  100%{
    opacity: 0;
    bottom: 20px;
  }
}

@keyframes rainiii{
  0%{
    opacity: 0;
    bottom: 100px;
    left: 0px;
  }
  72%
    opacity: 0;
    bottom: 100px;
    left: 0px;
  }
  73%
    opacity: 1;
    bottom: 15px;
    left: -10px;
  }
  74%
    opacity: 1;
    bottom: 25px;
    left: -8px;
  }
  80%
    opacity: 1;
    bottom: 25px;
    left: -8px;
  }
  81%
    opacity: 0;
    bottom: -15px;
    left: -28px;
  }
  100%{
    opacity: 0;
    bottom: 20px;
  }
}

@keyframes fade_in{
  0%{
    opacity: 0;
  }
  8%{
    opacity: 1;
  }
  9%{
    opacity: 1;
  }
  11%
    opacity: 1;
  }
  12%
    opacity: 0;
  }
  100%{
    oapcity: 0;
  }
}