[css-overflow-3] Fix bikeshed links

Author: frivoal

css-overflow-3/Overview.bs

@@ -53,6 +53,9 @@ spec:css-writing-modes-4; type:dfn; text:end
 spec:css-pseudo-4; type:selector; text:::first-line
 spec:css-pseudo-4; type:selector; text:::first-letter
 spec:css-display-3; type:property; text:display
+spec:css-sizing-3; type:property; text:max-height
+spec:css-box-4; type:dfn; text:content area
+spec:mediaqueries-3; type:value; text:print
 </pre>
 <!-- FIXME: the break-* link doesn't actually work! -->
 <pre class="anchors">
@@ -494,7 +497,7 @@ Scrollbars and Layout</h3>
 	When reserving space for a scrollar placed at the edge of an element's box,
 	the reserved space is inserted between the inner border edge
 	and the outer padding edge.
-	For the purpose of the [=background positioning area=] and [=background painting area=], however,
+	For the purpose of the <a spec=css-backgrounds>background positioning area</a> and <a spec=css-backgrounds>background painting area</a> however,
 	this reserved space is considered to be part of the [=padding box=].
 
 	<div class="example">
@@ -522,7 +525,7 @@ Scrollbars and Layout</h3>
 		then <code>&lt;aside></code> will be completely visible,
 		on the right padding-box edge adjacent to the scrollbars;
 		whereas the background image will be tucked underneath the scrollbars,
-		in the top right corner of the scrollbar-extended [=background positioning area=].
+		in the top right corner of the scrollbar-extended <a spec=css-backgrounds>background positioning area</a>.
 	</div>
 
 	When the box is intrinsically sized,