<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-type" content="text/html; charset=utf-8">
<style type="text/css" media="screen">
div {
-webkit-box-sizing: border-box;
}
.solid {
position: absolute;
width: 100px;
height: 100px;
background-color: green;
}
.opacity { opacity: .5; }
.a { top: 0px; left: 0px;}
.b { top: 200px; left: 200px;}
.c { top: 200px; left: 0px;}
.d { top: 0px; left: 200px;}
.composited {
will-change: transform;
}
* { margin: 0; padding: 0; }
</style>
</head>
<div class="composited opacity">
<div class="solid composited a">1</div>
<div class="solid composited b">2</div>
<div class="solid composited c">3</div>
<div class="solid composited d"></div>
</div>
</html>