<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
#box{
position: relative;
}
span{
position: absolute;
border: 8px solid #fff;
border-top: 8px solid transparent;
border-radius: 50%;
}
span:nth-child(1){
width: 80px;
height: 80px;
-webkit-animation: a 1s infinite linear;
}
span:nth-child(2){
width: 40px;
height: 40px;
left: 20px;
top: 20px;
-webkit-animation: b 0.5s infinite linear;
}
@-webkit-keyframes a{
0%{-webkit-transform: rotate(360deg); opacity: 1;}
50%{-webkit-transform: rotate(180deg); opacity: 0.5;}
100%{-webkit-transform: rotate(0deg); opacity: 1;}
}
@-webkit-keyframes b{
0%{-webkit-transform: rotate(0deg); opacity: 0.5;}
50%{-webkit-transform: rotate(180deg); opacity: 1;}
100%{-webkit-transform: rotate(360deg); opacity: 0.5;}
}
</style>
</head>
<body style="background-color: rosybrown;">
<div id="box">
<span></span>
<span></span>
</div>
</body>