纯CSS，多个半圆以中心点旋转

效果图：

html代码：

 <div  style="    background:#000; position: relative; width:300px; height:300px;">
     <img  src="http://res1.eqh5.com/o_1b8g6r3aa1l0s1ap250p11bk51gq.png?imageMogr2/thumbnail/721x721&gt;/strip" style="padding:9%;width: 82%; animation: rotateIn 3.5s ease 0s infinite both;">
     <img  src="http://res1.eqh5.com/o_1b8g6r3aa1l0s1ap250p11bk51gq.png?imageMogr2/thumbnail/642x642&gt;/strip" style="width: 73%;  padding:13.5%; animation: rotateIn 4s ease 0s infinite both;">
     <img  src="http://res1.eqh5.com/o_1b8g6q6om18tapg81ga4bvj3i8a.png?imageMogr2/thumbnail/642x642&gt;/strip" style="width: 73%;  padding:13.5%;  animation: rotateIn 2s ease 0s infinite both;">
     <img  src="http://res1.eqh5.com/o_1b8g6r3aa1l0s1ap250p11bk51gq.png?imageMogr2/thumbnail/761x761&gt;/strip" style="width: 86.5%;  padding:6.75%;  animation: rotateIn 6.5s ease 0s infinite both;">
 </div>

CSS代码：

@-webkit-keyframes rotateIn{from{-webkit-transform:rotate(0)}to{-webkit-transform:rotate(360deg)}}
 img{position: absolute;top:0px; left:0px;}

素材：