title: Extra Space in Nested ul in Firefox, but not Chrome
body: <p>I am attempting to make a vertical sidebar for a website. There are several main items in the <code>ul</code>, and if those items have subcategories, then a new <code>ul</code> gets nested within the main <code>ul</code> underneath its parent <code>li</code> (this is more obvious from the code below). In the latest version of Chrome this displays as it should, yet in the latest Firefox there is a space between the parent <code>li</code> and its corresponding subitems in the nested <code>ul</code>. Any thoughts on the cause? </p>
  
  <p>Here is the basic html:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
      &lt;html lang="en"&gt;
          &lt;head&gt;
          &lt;meta charset="utf-8" /&gt;
          &lt;title&gt;&lt;/title&gt;
          &lt;script&gt;
          &lt;/script&gt;
          &lt;style&gt;
          &lt;/style&gt;
          &lt;link rel="stylesheet" href="style.css" type="text/css"&gt;
          &lt;/head&gt;
  &lt;body&gt;
   &lt;ul class="navigation"&gt;
     &lt;li&gt;ITEM1&lt;/li&gt;
     &lt;li&gt;ITEM2&lt;/li&gt;
       &lt;ul class="navigation subitem"&gt;
         &lt;li&gt;subitem1&lt;/li&gt;
         &lt;li&gt;subitem2&lt;/li&gt;
         &lt;li&gt;subitem3&lt;/li&gt;
       &lt;/ul&gt;
     &lt;li&gt;ITEM3&lt;/li&gt;
    &lt;/ul&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>Here is the corresponding CSS:</p>
  
  <pre><code>.navigation {
      display: inline;
      width: 150px;
      margin-top: 5px;
      padding-left: 15px;
      text-align: right;
      vertical-align: middle;
  }
  
  .subitem {
      margin: 0px;
      vertical-align: top;
      top: 0px;
  
  }
  
  .navigation li {
      display: block;
      font-family: 'Oxygen';
      text-transform: uppercase;
      font-size: 1.5rem;
      margin-top: 15px;
  }
  
  .subitem li {
      font-size: 0.6em;
      margin-top: 3px;
      color: rgba(0, 0, 0, 0.9);
  
  }
  </code></pre>
  
  <p>If you load these in both Chrome and Firefox you should be able to see the difference.</p>