All About CSS Animation
https://www.kirupa.com/html5/all_about_css_animations.htm
by Avinashullal
HTML
<div id="mainContent">
<img id="bigcloud" alt="#" class="cloud" height="154" src="//www.kirupa.com/images/bigCloud.png" width="238">
</div>
CSS
#mainContent {
background-color: #A2BFCE;
border-radius: 4px;
padding: 10px;
width: 600px;
height: 300px;
overflow: hidden;
}
.cloud {
position: absolute;
}
#bigcloud {
animation: bobble 2s infinite;
margin-left: 100px;
margin-top: 15px;
}
@keyframes bobble {
0% {
transform: translate3d(50px, 40px, 0px);
animation-timing-function: ease-in;
}
50% {
transform: translate3d(50px, 50px, 0px);
animation-timing-function: ease-out;
}
100%{
transform: translate3d(50px, 40px, 0px)
}
}