[css-page-3] Add missing period

Author: xfq

css-page-3/Overview.bs

@@ -2385,7 +2385,7 @@ Changes</h2>
 	<ul>
 		<li>Imported the 'marks' and 'bleed' properties from [[CSS3GCPM]].
 		<li>Added ''bleed/auto'' as the initial value of 'bleed' and allowed it to apply even when 'marks' is ''marks/none''.
-		<li>Added JIS-B4 and JIS-B5
+		<li>Added JIS-B4 and JIS-B5.
 	</ul>
 
 <h2 class="no-num" id="acknowledgements">Acknowledgements</h2>