.main{
  position:absolute;
  top:50%;
  left:50%;
  width:100px;
  height:100px;
  margin:-50px;
  background-color:rgba(0,0,0,0.2);
  overflow:visible;
}
.father{
  position:absolute;
  top:50%;
  left:50%;
  width:100px;
  height:100px;
  margin:-50px;
  overflow:visible;
}
.content1{
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(50px,0px);
  background-color:rgba(0,0,255,0);
  overflow:hidden;
}
.content1:after{
  content:'';
  display:block;
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(-50px,50px);
  background-color:rgba(0,0,255,0.2);
}
.content2{
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(0px,50px);
  background-color:rgba(0,0,255,0);
  overflow:hidden;
}
.content2:after{
  content:'';
  display:block;
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(-50px,-50px);
  background-color:rgba(0,0,255,0.2);
}
.content3{
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(-50px,0px);
  background-color:rgba(0,0,255,0);
  overflow:hidden;
}
.content3:after{
  content:'';
  display:block;
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(50px,-50px);
  background-color:rgba(0,0,255,0.2);
}
.content4{
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(0px,-50px);
  background-color:rgba(0,0,255,0);
  overflow:hidden;
}
.content4:after{
  content:'';
  display:block;
  width:200px;
  height:200px;
  position:absolute;
  left:50%;
  top:50%;
  margin:-100px;
  border-radius:50%;
  -webkit-transform:translate(50px,50px);
  background-color:rgba(0,0,255,0.2);
}