title: Nested / Compounded roles: apply multiple roles to overlapping text
body: <p>In my <code>custom.css</code> file I have,</p>
  
  <pre><code>.bold {
      font-weight: bold;
  }
  
  .red {
      color:red;
  }
  </code></pre>
  
  <p>And in my <code>_.rst</code> file,</p>
  
  <pre><code>.. role:: bold
  
  .. role:: red
  </code></pre>
  
  <p>But if I try to nest/compound them, only the outermost role takes effect, e.g.</p>
  
  <hr>
  
  <p><code>:bold:`:red:`This is only bold``
  </code></p>
  
  <p><strong>This is only bold</strong></p>
  
  <hr>
  
  <p>Is there a way to combine these effects without defining a new (combined) role?</p>