Clarify that comment convention is normative <http://lists.w3.org/Archives/Public/www-style/2010Feb/0041.html>

Author: fantasai

css-style-attr/Overview.html

@@ -234,7 +234,8 @@ <h2 id=syntax><span class=secno>3. </span>Syntax and Parsing</h2>
   <p>The value of the styling attribute must match the syntax of the contents
    of a CSS <a
    href="http://www.w3.org/TR/CSS21/syndata.html#rule-sets">declaration
-   block</a>, whose formal grammar is given below in terms of the <a
+   block</a>, whose formal grammar is given below in the terms and
+   conventions of the <a
    href="http://www.w3.org/TR/CSS21/syndata.html#syntax">CSS core
    grammar</a>:
 

css-style-attr/Overview.src.html

@@ -122,7 +122,7 @@ <h2 id="syntax">Syntax and Parsing</h2>
 
 <p>The value of the styling attribute must match the syntax of the contents of
 a CSS <a href="http://www.w3.org/TR/CSS21/syndata.html#rule-sets">declaration
-block</a>, whose formal grammar is given below in terms of the
+block</a>, whose formal grammar is given below in the terms and conventions of the
 <a href="http://www.w3.org/TR/CSS21/syndata.html#syntax">CSS core grammar</a>:
 
 <pre>