<!DOCTYPE HTML>
<style>
#a, #b {
  width: 100px;
  height: 100px;
  background-color: grey;
  -moz-appearance: none;
  box-shadow: 4px 4px 3px black;
  border: none !important;
  position: absolute;
}

#a {
  top: 20px;
  left: 20px;
}

#b {
  top: 170px;
  left: 20px;
</style>

<div id="a">&nbsp;</div>
<div id="b">&nbsp;</div>