<!doctype HTML>
<html>
<head>
<style>
html {
background: lightpink;
}
div {
position: relative;
width: 200px;
height: 200px;
}
.outer {
background-color: blue;
box-shadow: -50px -50px 0px 0px rgba(0,0,0,1);
left: 100px;
top: 100px;
}
.inner {
background-color: red;
left: 50px;
top: 50px;
}
</style>
</head>
<body>
</body>
<div class="outer">
<div class="inner"></div>
</div>
</html>