title: BEM? Blocks inside blocks?
body: <p>A little unsure on when to start a new context in BEM.</p>
  
  <p>Should all child elements always reference the block element? </p>
  
  <p>For e.g.</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
      &lt;head&gt;
          &lt;meta charset="utf-8"&gt;
          &lt;title&gt;bem&lt;/title&gt;
      &lt;/head&gt;
      &lt;body&gt;
          &lt;div class="header"&gt;
              &lt;div class="header__left"&gt;
                  &lt;!-- Left column content --&gt;
              &lt;/div&gt;
              &lt;div class="header__search"&gt;
                  &lt;!-- Should this be attached to the header? Or a new context &lt;div class="search"&gt; as it can be used elsewhere on the site? --&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>Here the search is inside the 'header' div but should we really attach it to the header as this could be used elsewhere on the site?</p>
  
  <p>Do you have new blocks inside blocks?</p>
  
  <p>Cheers</p>