<!DOCTYPE html>
<style>
#target {
width: 220px;
height: 120px;
overflow: scroll;
}
#inner {
padding: 10px;
box-shadow: 10px 10px green inset;
height: 120px;
}
</style>
<div id="target">
<div id="inner">
Passes if green inset shadow is visible.
</div>
</div>