When giving e.g. a
Inspired by the other answers I created my own answer as well: https://jsfiddle.net/zoxgbcrg/1/
.shadow {
background-color: black !important;
width: 40px;
height: 40px;
box-shadow: 0px 0px 10px 5px #000;
margin-top: 35px;
margin-left: 35px;
position: absolute;
z-index: -1;
}
The trick is also to create an additional Note: it seems that of today (31.01.2016) Firefox and Chrome have a subtile rendering difference. So for Firefox https://jsfiddle.net/zoxgbcrg/ is creating the desired result, for Chrome I suggest https://jsfiddle.net/zoxgbcrg/1/:before
but a real DOM element that is moved by margin
.