<!--to host images on github-->
<!--type   https://raw.githubusercontent.com/username/repositoryname/branch/file
-->
<html>
  <body>
    <div class="sky">
    <div class="cloud"></div>
     </div>
<!--     <img src="https://raw.githubusercontent.com/claudz1/CodepenImages/master/bg-clouds.png" alt="" > -->
  </body>
</html>

body{
  padding:0;
  margin:0;
}
* { background:#C0DEED}
.cloud{
  background:url('https://raw.githubusercontent.com/claudz1/CodepenImages/master/bg-clouds.png') repeat-x;
  height:175px;
  width:100%;
  animation:cloudani 10s linear infinite;
}
@keyframes cloudani{
  from{
    background-position:0 0;
  }
  to{
    background-position:100% 0;
  }
}

External CSS

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External JavaScript

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