The :first-child

<pre><code>//the selector matches any &lt;p&gt; element that is the first child of any element
p:first-child {
  color: blue;
}</code></pre>

//the selector matches the first <i> element in all <p> elements

p i:first-child {
  color: blue;
}

//the selector matches all <i> elements in <p> elements 
//that are the first child of another element

p:first-child i {
  color: blue;
}