add note about nested fragments

README.md

@@ -219,6 +219,16 @@ The default fragment style is to start out invisible and fade in. This style can
 </section>
 ```
 
+Multiple fragments can be applied to the same element sequentially by wrapping it, this will fade in the text on the first step and fade it back out on the second.
+
+```
+<section>
+	<span class="fragment fade-out">
+		<span class="fragment fade-out">I'll fade in, then out</span>
+	</span>
+</section>
+```
+
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