<ul>
  <li>W3TR</li>
  <li>W3TR</li>
  <li>W3TR</li>
</ul>
<ul>
  <li>W3TR</li>
  <li>W3TR</li>
  <li>W3TR</li>
</ul>
<ul>
  <li>W3TR</li>
  <li>W3TR</li>
  <li>W3TR</li>
</ul>  
$("li:first-of-type").css("background-color", "red");

External CSS

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External JavaScript

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