Fixing spelling mistake.

index.html

@@ -299,7 +299,7 @@ function linkify( selector ) {
 				<section>
 					<h2>Take a Moment</h2>
 					<p>
-						Press b or period on your keyboard to enter the 'paused' mode. This mode is helpful when you want to take disctracting slides off the screen
+						Press b or period on your keyboard to enter the 'paused' mode. This mode is helpful when you want to take distracting slides off the screen
 						during a presentation.
 					</p>
 				</section>