Fix markup error.

Author: tabatkins

css-grid-1/Overview.bs

@@ -3430,7 +3430,7 @@ Grid Container Baselines</h3>
 			according to the rules of its <a>alignment context</a>.
 	</ol>
 
-	<dfn export lt="grid order|grid-modified document order">'grid-modified document order (grid order)</dfn>
+	<dfn export lt="grid order|grid-modified document order">Grid-modified document order (grid order)</dfn>
 	is the order in which <a>grid items</a> are encountered
 	when traversing the grid's <a>grid cells</a>.
 	If two items are encountered at the same time,