[fonts-4] Redefine @font-face with a Syntax grammar, and rewrap surrounding paragraphs.

Author: tabatkins

css-fonts-4/Overview.bs

@@ -1220,54 +1220,41 @@ Font Resources</h2>
 <h3 id="font-face-rule">
 The <dfn id="at-font-face-rule">''@font-face''</dfn> rule</h3>
 
-The ''@font-face'' rule allows for linking to fonts that are
-automatically fetched and activated when needed. This allows authors to select
-a font that closely matches the design goals for a given page
-rather than limiting the font choice to a set of fonts available
-on a given platform. A set of font descriptors define the location of a font
-resource, either locally or externally, along with the style characteristics of
-an individual face. Multiple ''@font-face'' rules can be used to construct
-font families with a variety of faces. Using CSS font matching rules, a
-user agent can selectively download only those faces that are needed for
-a given piece of text.
-
-The ''@font-face'' rule consists of the ''@font-face'' at-keyword followed
-by a block of descriptor declarations. In terms of the grammar, this
-specification defines the following productions:
+The ''@font-face'' rule allows for linking to fonts
+that are automatically fetched and activated when needed.
+This allows authors to select a font
+that closely matches the design goals for a given page
+rather than limiting the font choice
+to a set of fonts available on a given platform.
+A set of font descriptors define the location of a font resource,
+either locally or externally,
+along with the style characteristics of an individual face.
+Multiple ''@font-face'' rules can be used to construct font families with a variety of faces.
+Using CSS font matching rules,
+a user agent can selectively download
+only those faces that are needed for a given piece of text.
+
+It's syntax is:
 
-<pre>
-	<dfn>font_face_rule</dfn>
-	  : <a>FONT_FACE_SYM</a> <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* '{' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* <a>descriptor_declaration</a>? [ ';' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* <a>descriptor_declaration</a>? ]* '}' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>*
-	  ;
-
-	<dfn>descriptor_declaration</dfn>
-	  : <a href="https://www.w3.org/TR/CSS21/grammar.html#grammar"><a>property</a></a> ':' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* <a href="https://www.w3.org/TR/CSS21/grammar.html#grammar"><a>expr</a></a>
-	  ;
-</pre>
-
-The following new definitions are introduced:
-
-<pre>
-	-    -|\\0{0,4}2d(\r\n|[ \t\r\n\f])?
-
-	F    f|\\0{0,4}(46|66)(\r\n|[ \t\r\n\f])?
+<pre class=prod>
+@font-face {
+	<<declaration-list>>
+}
 </pre>
 
-The following new token is introduced:
-
-<pre>@{F}{O}{N}{T}{-}{F}{A}{C}{E} {return <dfn>FONT_FACE_SYM</dfn>;}</pre>
+The ''@font-face'' rule accepts the descriptors defined in this specification.
 
-Each ''@font-face''
-rule specifies a value for every font descriptor, either implicitly or
-explicitly. Those not given explicit values in the rule take the initial
-value listed with each descriptor in this specification. These
-descriptors apply solely within the context of the ''@font-face'' rule in
-which they are defined, and do not apply to document language elements.
-There is no notion of which elements the descriptors apply to or whether
-the values are inherited by child elements.  When a given descriptor occurs
-multiple times in a given ''@font-face'' rule, only the last
-descriptor declaration is used and all prior declarations for that
-descriptor are ignored.
+Each ''@font-face''rule specifies a value for every font descriptor,
+either implicitly or explicitly.
+Those not given explicit values in the rule
+take the initial value listed with each descriptor in this specification.
+These descriptors apply solely within the context of the ''@font-face'' rule in which they are defined,
+and do not apply to document language elements.
+There is no notion of which elements the descriptors apply to
+or whether the values are inherited by child elements.
+When a given descriptor occurs multiple times in a given ''@font-face'' rule,
+only the last descriptor declaration is used
+and all prior declarations for that descriptor are ignored.
 
 <div class="example">
 	To use a downloadable font called Gentium:
@@ -2727,7 +2714,7 @@ followed by a block of descriptor declarations.
 It has the following syntax:
 
 <pre class=prod>
-	@font-palette-values {
+	@font-palette-values <<custom-ident>> {
 		<<declaration-list>>
 	}
 </pre>