Changed 'as' to 'by' for clarity.

Author: tabatkins

css3-images/Overview.html

@@ -1027,7 +1027,7 @@ <h4 class=no-toc id=radial-gradient-syntax><span class=secno>4.2.1. </span>
    <dt id=radial-position><dfn id=ltpositiongt>&lt;position&gt;</dfn>
 
    <dd>Determines the center of the gradient. The <a
-    href="#ltpositiongt"><i>&lt;position&gt;</i></a> notation is defined as
+    href="#ltpositiongt"><i>&lt;position&gt;</i></a> notation is defined by
     the positioning syntax of &lsquo;<code class=css><a
     href="http://www.w3.org/TR/css3-background/#the-background-position">background-position</a></code>&rsquo;
     and is resolved in the same way, using the center-point as the subject

css3-images/Overview.src.html

@@ -629,7 +629,7 @@ <h4 class='no-toc' id='radial-gradient-syntax'>
 
 		<dt id='radial-position'><dfn>&lt;position&gt;</dfn></dt>
 		<dd>Determines the center of the gradient. The <i>&lt;position&gt;</i> notation
-		is defined as the positioning syntax of
+		is defined by the positioning syntax of
 		'<a href="http://www.w3.org/TR/css3-background/#the-background-position">background-position</a>'
 		and is resolved in the same way, using the center-point as the subject and
 		the content box as the positioning area. [[!CSS21]] [[!CSS3BG]]