How do I create an underline when I hover over links in nav bar?
<p>I want to create an underline when I hover over the links in my navigation bar. I'm not sure which id I should be targeting. Here's my JFiddle: <a href="https://jsfiddle.net/gzycz4h8/" rel="nofollow">https://jsfiddle.net/gzycz4h8/</a></p>

<p>Thanks in advance.</p>

<pre><code>&lt;ul id="nav"&gt;
  &lt;li&gt;&lt;a href="#"&gt;About&lt;/a&gt;&lt;/li&gt;
  &lt;li&gt;&lt;a href="#"&gt;Writing&lt;/a&gt;&lt;/li&gt;
  &lt;li&gt;&lt;a href="#"&gt;Multimedia&lt;/a&gt;&lt;/li&gt;
  &lt;li&gt;&lt;a href="#"&gt;Resume&lt;/a&gt;&lt;/li&gt;
  &lt;li&gt;&lt;a href="#"&gt;Contact&lt;/a&gt;&lt;/li&gt;
&lt;/ul&gt;
</code></pre>