PrinceXML

HTML

<div>
  <span>C
    <span>B
      <span>A</span>
    </span>
  </span>
</div>

CSS

div {
   display: inline-block;
   border: 1px solid blue;
}
span {
  display: inline-block;
  width: 100%;
  border: 1px solid red;
}