Add note about reduced interactive area due to border-radius. <http://lists.w3.org/Archives/Public/www-style/2012Jun/0445.html>

Author: fantasai

css3-background/Overview.html

@@ -2878,8 +2878,16 @@ <h3 id=corner-clipping><span class=secno>5.3. </span>Corner Clipping</h3>
    class=property>overflow</code>’ other than ‘<code
    class=css>visible</code>’) also must clip to the curve. The content of
    replaced elements is always trimmed to the content edge curve. Also, the
-   area outside the curve of the border edge does not accept mouse events on
-   behalf of the element.
+   area outside the curve of the border edge does not accept pointer events
+   on behalf of the element.
+
+  <p class=note>As ‘<a href="#border-radius"><code
+   class=property>border-radius</code></a>’ reduces the interactive area of
+   an element authors should make sure the remaining interactive area
+   conforms to recommended minima for the platforms they target; in
+   particular, conforming to recommended minimum touch target sizes may
+   require larger widths and heights when ‘<a href="#border-radius"><code
+   class=property>border-radius</code></a>’ is used.
 
   <div class=example>
    <p>This example adds appropriate padding, so that the contents do not

css3-background/Overview.src.html

@@ -2050,8 +2050,14 @@ <h3 id="corner-clipping">Corner Clipping</h3>
 Other effects that clip to the border or padding edge (such as 'overflow'
 other than ''visible'') also must clip to the curve. The content of
 replaced elements is always trimmed to the content edge curve.
-Also, the area outside the curve of the border edge does not accept mouse
-events on behalf of the element.
+Also, the area outside the curve of the border edge does not
+accept pointer events on behalf of the element.
+
+<p class="note">As 'border-radius' reduces the interactive area of an element
+authors should make sure the remaining interactive area conforms
+to recommended minima for the platforms they target;
+in particular, conforming to recommended minimum touch target sizes
+may require larger widths and heights when 'border-radius' is used.
 
 <div class=example>
 <p>This example adds appropriate padding, so that the