[css-background] spread clarification

Author: fantasai

css-backgrounds/Overview.html

@@ -4080,19 +4080,19 @@ <h3 id=the-box-shadow><span class=secno>7.2. </span>Drop Shadows: the ‘<a
    href="#border-image"><code class=property>border-image</code></a>’ does
    not affect the shape of the box-shadow.
 
-  <p>If a spread distance is defined, the shadow is expanded outward (for
-   normal shadows) or contracted inward (for ‘<a href="#inset"><code
-   class=css>inset</code></a>’ shadows) by the spread distance in the
-   direction normal to the original shadow perimeter. Alternatively, the UA
-   may approximate the transformed shadow perimeter shape by outsetting
-   (insetting, for inner shadows) the shadow's straight edges by the spread
-   distance and increasing (decreasing, for inner shadows) and flooring at
-   zero the corner radii by the same amount. For corners with a zero
-   border-radius, however, the corner must remain sharp—the operation is
-   equivalent to scaling the shadow shape. In any case, the effective width
-   and height of the shadowed shape is floored at zero. (A zero-sized
-   shadowed shape would cause an outer shadow to disappear, and an inner
-   shadow to cover the entire padding-box.)
+  <p>If a spread distance is defined, the shadow perimenter is expanded
+   outward (for normal shadows) or contracted inward (for ‘<a
+   href="#inset"><code class=css>inset</code></a>’ shadows) by the spread
+   distance in the direction normal to the original shadow perimeter.
+   Alternatively, the UA may approximate the transformed shadow perimeter
+   shape by outsetting (insetting, for inner shadows) the shadow's straight
+   edges by the spread distance and increasing (decreasing, for inner
+   shadows) and flooring at zero the corner radii by the same amount. For
+   corners with a zero border-radius, however, the corner must remain
+   sharp—the operation is equivalent to scaling the shadow shape. In any
+   case, the effective width and height of the shadowed shape is floored at
+   zero. (A zero-sized shadowed shape would cause an outer shadow to
+   disappear, and an inner shadow to cover the entire padding-box.)
 
   <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;

css-backgrounds/Overview.src.html

@@ -2940,7 +2940,7 @@ <h3 id="the-box-shadow">Drop Shadows: the 'box-shadow' property</h3>
 affect the shape of the box-shadow.
 
 <p>If a spread distance is defined,
-the shadow is expanded outward (for normal shadows) or contracted inward (for ''inset'' shadows)
+the shadow perimenter is expanded outward (for normal shadows) or contracted inward (for ''inset'' shadows)
 by the spread distance in the direction normal to the original shadow perimeter.
 Alternatively, the UA may approximate the transformed shadow perimeter shape by
 outsetting (insetting, for inner shadows) the shadow's straight edges by the spread distance