Correct scrollbar space description

css-overflow-3/Overview.bs

@@ -728,11 +728,11 @@ Scrollbars and Layout</h2>
 <h3 id="scrollbar-sizing">
 Scrollbar Contributions to Sizing</h3>
 
-	When reserving space for a scrollbar 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 <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=].
+	The space reserved for the scrollbar is located between the 
+	padding area and the border area of the scroll container box.
+	However, for the purpose of the <a spec=css-backgrounds>background positioning area</a> 
+	and <a spec=css-backgrounds>background painting area</a>, this 
+	reserved space is treated as part of the [=padding area=].
 
 	<div class="example">
 		In the following document fragment,