<html>
<head>
<style>
div.test {
  width: 500px;
  height: 500px;
  box-shadow: inset 70px 70px 50px 0px black;
  position: absolute;
}

div.cover {
  width: 500px;
  height: 500px;
  background-color: black;
  position: absolute;
  margin-top: 0px;
  margin-left: 30px;
}
</style>
<body>
<div class="test">
</div>
<div class="cover">
</div>
</body>
</html>