clarify that zero can be followed by a unit identifier in a better way (credit: dbaron)

Author: annevk

css3-mediaqueries/Overview.html

@@ -24,13 +24,13 @@
 
    <h1 id=media-queries>Media Queries</h1>
 
-   <h2 class="no-num no-toc" id=w3c-working>Editor's Draft 1 September 2008</h2>
+   <h2 class="no-num no-toc" id=w3c-working>Editor's Draft 8 September 2008</h2>
 
    <dl>
     <dt>This version:
 
     <dd><a
-     href="http://www.w3.org/TR/2008/ED-css3-mediaqueries-20080901/">http://www.w3.org/TR/2008/ED-css3-mediaqueries-20080901/</a>
+     href="http://www.w3.org/TR/2008/ED-css3-mediaqueries-20080908/">http://www.w3.org/TR/2008/ED-css3-mediaqueries-20080908/</a>
 
     <dt>Latest version:
 
@@ -569,7 +569,7 @@ <h2 id=syntax><span class=secno>3. </span>Syntax</h2>
    rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>
 
   <pre>media_query_list
- : S* media_query [ &#39;,&#39; S* media_query]* | S*
+ : S* media_query [ ',' S* media_query]* | S*
  ;
 media_query
  : [ONLY | NOT]? S* media_type S* [ AND S* expression ]*
@@ -579,7 +579,7 @@ <h2 id=syntax><span class=secno>3. </span>Syntax</h2>
  : IDENT
  ;
 expression
- : &#39;(&#39; S* media_feature S* [&#39;:&#39; S* value]? &#39;)&#39; S*
+ : '(' S* media_feature S* [':' S* value]? ')' S*
  ;
 media_feature
  : IDENT
@@ -746,11 +746,12 @@ <h2 id=media1><span class=secno>4. </span>Media features</h2>
     features, on the other hand, can also be used without a value. For a
     media feature <var>feature</var>, <code>(<var>feature</var>)</code> will
     evaluate to true if <code>(<var>feature</var>:<var>x</var>)</code> will
-    evaluate to true for a value <var>x</var> other than zero, including e.g.
-    <code>0</code>, <code>0px</code>, and <code>0em</code>. Media features
-    that are prefixed by min/max cannot be used without a value. When a media
-    feature prefixed with min/max is used without a value it makes the media
-    query malformed.
+    evaluate to true for a value <var>x</var> other than zero or zero
+    followed by a unit identifier (i.e., other than <code>0</code>,
+    <code>0px</code>, <code>0em</code>, etc.). Media features that are
+    prefixed by min/max cannot be used without a value. When a media feature
+    prefixed with min/max is used without a value it makes the media query
+    malformed.
 
    <li>Properties may accept more complex values, e.g., calculations that
     involve several other values. Media features only accept single values:

css3-mediaqueries/Overview.src.html

@@ -432,7 +432,7 @@ <h2>Syntax</h2>
 <code>medium</code> production from CSS2. [[!CSS21]]</p>
 
 <pre>media_query_list
- : S* media_query [ &#39;,&#39; S* media_query]* | S*
+ : S* media_query [ ',' S* media_query]* | S*
  ;
 media_query
  : [ONLY | NOT]? S* media_type S* [ AND S* expression ]*
@@ -442,7 +442,7 @@ <h2>Syntax</h2>
  : IDENT
  ;
 expression
- : &#39;(&#39; S* media_feature S* [&#39;:&#39; S* value]? &#39;)&#39; S*
+ : '(' S* media_feature S* [':' S* value]? ')' S*
  ;
 media_feature
  : IDENT
@@ -603,11 +603,11 @@ <h2 id="media1">Media features</h2>
 features, on the other hand, can also be used without a value. For a media
 feature <var>feature</var>, <code>(<var>feature</var>)</code> will evaluate
 to true if <code>(<var>feature</var>:<var>x</var>)</code> will evaluate to
-true for a value <var>x</var> other than zero, including e.g.
-<code>0</code>, <code>0px</code>, and <code>0em</code>. Media features that
-are prefixed by min/max cannot be used without a value. When a media feature
-prefixed with min/max is used without a value it makes the media query
-malformed.</li>
+true for a value <var>x</var> other than zero or zero followed by a unit
+identifier (i.e., other than <code>0</code>, <code>0px</code>,
+<code>0em</code>, etc.). Media features that are prefixed by min/max cannot
+be used without a value. When a media feature prefixed with min/max is used
+without a value it makes the media query malformed.</li>
 
 <li>Properties may accept more complex values, e.g., calculations that
 involve several other values. Media features only accept single