JSFiddle - React, Tailwind, and code Playground

HTML

<div class="">
    <div class="pic u1"></div>
    <div class="pic u2"></div>
    <div class="pic u3"></div>
</div>

CSS

@-webkit-keyframes scrollem {
  0% {
    background-position-x: 0px;
  }

  100% {
    background-position-x: -2000000px;
  }
}

@-moz-keyframes scrollem {
 0% {
    background-position-x: 0px;
  }

  100% {
    background-position-x: -2000000px;
  }
}

@-ms-keyframes scrollem {
 0% {
    background-position-x: 0px;
  }

  100% {
    background-position-x: -2000000px;
  }
}

@keyframes scrollem {
 0% {
    background-position-x: 0px;
  }

  100% {
    background-position-x: -2000000px;
  }
}


.pic {
    width:100%;
    height:400px;
    position:absolute;
  background-repeat: repeat-x;	
	background-size: cover !important;  
	-webkit-animation-timing-function: linear;
	-webkit-animation-name: scrollem;
	-webkit-animation-iteration-count: infinite;	
	-webkit-animation-direction: normal;

	-moz-animation-timing-function: linear;
	-moz-animation-name: scrollem;
	-moz-animation-iteration-count: infinite;
	-moz-animation-direction: normal;		

	-ms-animation-timing-function: linear;
	-ms-animation-name: scrollem;
	-ms-animation-iteration-count: infinite;
	-ms-animation-direction: normal;	

	animation-timing-function: linear;
	animation-name: scrollem;
	animation-iteration-count: infinite;
	animation-direction: normal;    
    
    
    
}
.u1 {
    background: transparent url('http://i.telegraph.co.uk/multimedia/archive/02387/ufo_2387810b.jpg');
    	-webkit-animation-duration: 100000s;
	-moz-animation-duration: 100000s;
	-ms-animation-duration: 100000s;
	animation-duration: 100000s;
}
.u2 {
    top:100px;
    background: transparent url('http://www.techi.com/wp-content/uploads/2012/11/UFO-4.jpg');
        	-webkit-animation-duration: 200000s;
	-moz-animation-duration: 200000s;
	-ms-animation-duration: 200000s;
	animation-duration: 200000s;
}
.u3 {
    top:200px;
    background: transparent url('http://www.blisstree.com/wp-content/uploads/2013/07/UFO-EARTHLINGS.jpg') ;
    	-webkit-animation-duration: 300000s;
	-moz-animation-duration: 300000s;
	-ms-animation-duration:...