Add example, remove stray definition, simplify note.

Author: fantasai

css3-images/Overview.html

@@ -1017,8 +1017,14 @@ <h4 class=no-toc id=radial-gradient-syntax><span class=secno>4.2.1. </span>
 &lt;radial-gradient> = radial-gradient(
   [ [ &lt;shape> || &lt;size> ] [ at &lt;position> ]? ,]?
   &lt;color-stop> [ , &lt;color-stop> ]+
-)
-&lt;extent-keyword> = closest-corner | closest-side | farthest-corner | farthest-side</pre>
+)</pre>
+
+  <div class=example>
+   <p>Here is an example of a circular radial gradient 5em wide and
+    positioned with its center in the top left corner:
+
+   <pre>radial-gradient(5em circle at top left, yellow, blue)</pre>
+  </div>
 
   <p>The arguments are defined as follows:
 
@@ -1139,12 +1145,7 @@ <h4 class=no-toc id=radial-gradient-syntax><span class=secno>4.2.1. </span>
   </dl>
 
   <div class=note>
-   <p>The grammar listed above is kept deliberately simple for readability
-    purposes, with some details instead expressed in the prose. All of the
-    details can be expressed directly in the grammar, however, and such a
-    grammar is presented here for use by implementors and others writing
-    parsers. It is officially non-normative, but should match the same set of
-    strings that the normative grammar does when augmented with the prose.
+   <p>Expanded with the above definitions, the grammar becomes:
 
    <pre>
 &lt;radial-gradient> = radial-gradient(

css3-images/Overview.src.html

@@ -624,8 +624,13 @@ <h4 class='no-toc' id='radial-gradient-syntax'>
 &lt;radial-gradient> = radial-gradient(
   [ [ &lt;shape> || &lt;size> ] [ at &lt;position> ]? ,]?
   &lt;color-stop> [ , &lt;color-stop> ]+
-)
-&lt;extent-keyword> = closest-corner | closest-side | farthest-corner | farthest-side</pre>
+)</pre>
+
+	<div class=example>
+		<p>Here is an example of a circular radial gradient 5em wide and
+		positioned with its center in the top left corner:
+		<pre>radial-gradient(5em circle at top left, yellow, blue)</pre>
+	</div>
 
 	<p>The arguments are defined as follows:
 
@@ -706,7 +711,7 @@ <h4 class='no-toc' id='radial-gradient-syntax'>
 	</dl>
 
 	<div class='note'>
-		<p>The grammar listed above is kept deliberately simple for readability purposes, with some details instead expressed in the prose.  All of the details can be expressed directly in the grammar, however, and such a grammar is presented here for use by implementors and others writing parsers.  It is officially non-normative, but should match the same set of strings that the normative grammar does when augmented with the prose.
+		<p>Expanded with the above definitions, the grammar becomes:
 
 		<pre>
 &lt;radial-gradient> = radial-gradient(