CSS3 gives us more power to select elements based upon where they sit in the structure of the DOM.

Let's consider a common design treatment; we're working on the navigation bar for a larger viewport and we want to have all but the last link over on the left.

Historically, we would have needed to solve this problem by adding a class name to the last link so that we could select it, like this:

<nav class="nav-Wrapper">
  <a href="/home" class="nav-Link">Home</a>
  <a href="/About" class="nav-Link">About</a>
  <a href="/Films" class="nav-Link">Films</a>
  <a href="/Forum" class="nav-Link">Forum</a>
  <a href="/Contact-Us" class="nav-Link nav-LinkLast">Contact Us</a>
</nav>

This in itself can be problematic. For example, sometimes, just getting a content management system to add a class to a final list item can be frustratingly difficult. Thankfully, in those eventualities, it's no longer a concern...