<!DOCTYPE html>

<html>
<head>
    <style>
        .parent {
            position: absolute;
            height: 100px;
            width: 500px;
            margin: 50px;
            background: silver;
            clip: rect(0px, 520px, 600px, -20px); /* top, right, bottom, left */
            -webkit-transform: translateZ(0);
        }        

        .child {
            position: absolute;
            top: 50px;
            height: 100px;
            width: 400px;
            background: #ffea61;
            box-shadow: 0 0 50px black;
        }
    </style>
</head>
<body>
    <div class="shared parent">
      <div class="shared child"></div>
    </div>
</body>
</html>