<!DOCTYPE html>
<html lang="en">
<head>
<style>
* {padding: 0; margin: 0}
#d {
    width: 180px;
    height: 180px;
    border: 1px solid black;
    background-color: red;
}
#clip {
    width: 160px;
    height: 160px;
    margin: 10px;
    background-color: green;
    -webkit-clip-path: url(#c2);
}
#clip-ref {
    width: 32px;
    height: 32px;
    margin: 74px;
    background-color: green;
}
svg { display: block; }
</style>
</head>
<body>
<svg height="100" width="100">
<clipPath id="c2" clipPathUnits="userSpaceOnUse">
  <rect x="64" y="64" width="32" height="32"/>
</clipPath>
</svg>
<div id="d"><div id="clip"></div></div>
</body>
</html>