<!DOCTYPE html>
<html>
<head>
<style>
#myDIV {
position: absolute;
top: 200px;
width: 300px;
height: 150px;
background-color: lightblue;
border: 1px solid black;
animation: mymove 5s infinite;
}
#DIV2 {
position: absolute;
top: 180px;
left: 30px;
width: 300px;
height: 150px;
background-color: coral;
border: 1px solid black;
}
@keyframes mymove {
50% {opacity: 0;}
}
</style>
</head>
<body>
<h1>Animation of opacity</h1>
<p>The opacity property is <em>animatable</em> in CSS.</p>
<p>Change the opacity of the blue DIV element from 1 to 0, and back to 1:<p>
<div id="DIV2">
<h1>Voila!</h1>
</div>