<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style type="text/css">
.div1{
width:300px;
height: 300px;
background-color: red;
text-align: center;
}
.con {
height: 300px;
display: inline-block;
vertical-align: middle;
}
span{
vertical-align: middle;
height: 300px;
}
.div2{
width:30px;
height: 30px;
display: inline-block;
vertical-align: middle;
background-color: green;
text-align: center;
}
</style>
</head>
<body>
<div class="div1">
<div class="con"></div>
<span></span>
<div class="div2"></div>
</div>
</body>
</html>
