[css-values] Editorial cleanup of URL section.

Author: fantasai

css-values/Overview.bs

@@ -508,7 +508,6 @@ Resource Locators: the <<url>> type</h3>
 
 	<pre class="prod"><dfn id="url-value">&lt;url></dfn> = url( <<string>> <<url-modifier>>* )</pre>
 
-
 	<div class="example">
 		Below is an example of a URL being used as a background image:
 
@@ -518,15 +517,29 @@ Resource Locators: the <<url>> type</h3>
 	In addition to the syntax defined above,
 	a <<url>> can sometimes be written in other ways:
 
-	* For legacy reasons,
-		a <<url>> can be written without quotation marks around the URL itself.
-		This syntax is <a lt="consume a url token" spec=css-syntax-3>specially-parsed</a>,
-		and produces a <<url-token>> rather than a <a>function</a> syntactically. [[!CSS3SYN]]
-	* Some CSS contexts, such as ''@import'', allow a <<url>> to be represented by a <<string>> instead.
-		This behaves identically to writing a ''url()'' function containing that string.
-
-	Because these alternate ways of writing a <<url>> are not <a>functional notations</a>,
-	they cannot accept any <<url-modifier>>s.
+	* A <<url>> can be written without quotation marks around the URL itself.
+		(This syntax is <a lt="consume a url token" spec=css-syntax-3>specially-parsed</a>
+		as a <<url-token>>. [[!CSS3SYN]])
+
+		<div class="example">
+			For example, the following declarations are identical:
+			<pre>
+				background: url("http://www.example.com/pinkish.gif");
+				background: url(http://www.example.com/pinkish.gif);
+            </pre>
+		</div>
+
+	* Some CSS contexts (such as ''@import'') allow a <<url>> to be represented by a bare <<string>>,
+		without the ''url()'' wrapper.
+		In such cases the string behaves identically to a ''url()'' function containing that string.
+
+		<div class="example">
+			For example, the following statements are identical:
+			<pre>
+				@import url("base-theme.css");
+				@import "base-theme.css";
+			</pre>
+		</div>
 
 	Note: The special parsing rules for the legacy quotation-mark&ndash;less <<url>> syntax
 	means that parentheses, <a href="https://www.w3.org/TR/css-syntax/#whitespace">whitespace</a> characters,
@@ -537,8 +550,8 @@ Resource Locators: the <<url>> type</h3>
 	it might also be possible to write these characters as URL-escapes
 	(e.g. ''url(open%28parens)'' or ''url(close%29parens)'')
 	as described in [[URL]].
-	(If written as a normal function containing a string, ordinary string escaping rules apply;
-		only newlines and the character used to quote the string need to be escaped.)
+	Alternately, the URL can be quoted as a string,
+	in which case only newlines and the character used to quote the string need to be escaped.
 
 <h4 id="relative-urls">
 Relative URLs</h4>
@@ -640,11 +653,13 @@ URL Modifiers</h4>
 
 	The ''url()'' function supports specifying additional <dfn>&lt;url-modifier></dfn>s,
 	which change the meaning or the interpretation of the URL somehow.
-	A <<url-modifier>> is either an <<ident>> or a <a>function</a>.
+	A <<url-modifier>> is either an <<ident>> or a <a>functional notation</a>.
 
 	This specification does not define any <<url-modifier>>s,
 	but other specs may do so.
 
+	Note: A <<url>> that is either unquoted or not wrapped in ''url()'' notation
+	cannot accept any <<url-modifier>>s.
 
 <h2 id="numeric-types">
 Numeric Data Types</h2>