Child combinator A > B

A child combinator describes a childhood relationship between two elements.

Syntax

A > B{ properties }

A child combinator is made of the "greater-than sign" (>) character and separates two sequences of simple selectors.
For information on selecting the first child of an element, please see the section on the :first-child pseudo-class above.

[style.css]

 h1{
   font-size: 1.1em;
 }
 h1 > .myclass{
   font-style: italic;
 }
 h1 > span > em{
   color: red;
 }

[index.html]

<body>
<h1>This <span class="myclass">headline
is <em>very</em> important</span>
</h1>
</body>

The CSS Selectors Level 3 specification defines the child combinator in 8.2. Child combinators.