positive -> non-zero

Author: fantasai

css3-background/Overview.html

@@ -3773,7 +3773,7 @@ <h3 id=the-box-shadow><span class=secno>6.2. </span>The &lsquo;<a
    zero. (A zero-sized shadow shape would cause an outer shadow to disappear,
    and an inner shadow to cover the entire padding-box.)
 
-  <p>A positive blur distance indicates that the resulting shadow should be
+  <p>A non-zero blur distance indicates that the resulting shadow should be
    blurred, such as by a Gaussian filter. The exact algorithm is not defined;
    however for a long, straight shadow edge, this should create a color
    transition the length of the blur distance that is perpendicular to and

css3-background/Overview.src.html

@@ -2741,7 +2741,7 @@ <h3 id="the-box-shadow">The 'box-shadow' property</h3>
 floored at zero. (A zero-sized shadow shape would cause an outer shadow
 to disappear, and an inner shadow to cover the entire padding-box.)
 
-<p>A positive blur distance indicates that the resulting shadow should
+<p>A non-zero blur distance indicates that the resulting shadow should
 be blurred, such as by a Gaussian filter. The exact algorithm is not
 defined; however for a long, straight shadow edge, this should create
 a color transition the length of the blur distance that is perpendicular