[css-inline-3][editorial] Add line break

Author: fantasai

css-inline-3/Overview.bs

@@ -1077,7 +1077,8 @@ Text Edge Metrics: the 'line-fit-edge' property</h3>
 	expands to
 
 	<pre class=prod>
-		<<text-edge>> = [ text | cap | ex | ideographic | ideographic-ink ] [ text | alphabetic | ideographic | ideographic-ink ]?
+		<<text-edge>> = [ text | cap | ex | ideographic | ideographic-ink ]
+		              [ text | alphabetic | ideographic | ideographic-ink ]?
 	</pre>
 
 	The first value specifies the text [=over=] edge;