title: nesting other html tags inside ul except li
body: <p>Are these code pieces syntactically correct? I am using first code piece to build a navigation (nesting header tag inside ul). If it is wrong or it is a bad practice what are the drawbacks.  </p>
  
  <pre><code>&lt;ul class="site-title left"&gt;
    &lt;header&gt;
     &lt;li&gt;&lt;h1&gt;site title&lt;/h1&gt;&lt;/li&gt;
    &lt;/header&gt;                         
  &lt;/ul&gt;
  </code></pre>
  
  <p>and </p>
  
  <pre><code>&lt;ul class="site-title left"&gt;
    &lt;span&gt;
     &lt;li&gt;&lt;h1&gt;site-title&lt;/h1&gt;&lt;/li&gt;
    &lt;/span&gt;                           
  &lt;/ul&gt;
  </code></pre>