<!DOCTYPE html>
<style>
div {
  width: 0px;
  font-family: Ahem;
  font-size: 20px;
  color: green;
}
</style>
<div> X</div>
<div> <span>X</span></div>
<div><span> X</span></div>
<div> <span> X</span></div>
<div> <span style="margin: 20px;"> X</span></div>
<div> <span style="padding: 20px;"> X</span></div>
<div> <span><span>X</span></span></div>
<div> <span></span><span><span>X</span></span></div>
<div><span></span> <span></span><span><span>X</span></span></div>
<div><span></span><span></span> <span><span>X</span></span></div>
<div><span></span><span></span><span> <span>X</span></span></div>
<div><span></span><span></span><span><span> X</span></span></div>
<div><span></span><span></span><span><span style="margin: 20px"> X</span></span></div>
<div><span></span><span></span><span><span style="padding: 20px"> X</span></span></div>
