[css-mixins] Tweak the definitions a little to be friendlier cross-spec.

Author: tabatkins

css-mixins-1/Overview.bs

@@ -101,27 +101,28 @@ The ''@function'' rule defines a [=custom function=],
 and its syntax is:
 
 <pre class="prod def" nohighlight>
-@function <<function-name>> [ ( <<parameter-list>> ) ]?
-	[ using ( <<dependency-list>> ) ]?
-	[ returns <<type>> ]?
+&lt;@function> = @function <<function-name>> [ ( <<function-parameter-list>> ) ]?
+	[ using ( <<function-dependency-list>> ) ]?
+	[ returns <<css-type>> ]?
 {
 	<<declaration-rule-list>>
 }
 
 <dfn><<function-name>></dfn> = <<dashed-ident>>
-<dfn><<parameter-list>></dfn> = <<parameter>>#
-<dfn><<dependency-list>></dfn> = <<parameter>>#
-<dfn><<type>></dfn> = <<syntax-component>> | type( <<syntax>> )
-<dfn><<parameter>></dfn> = <<custom-property-name>> <<type>>? [ : <<declaration-value>> ]?
+<dfn><<function-parameter-list>></dfn> = <<function-parameter>>#
+<dfn><<function-dependency-list>></dfn> = <<function-parameter>>#
+<dfn><<function-parameter>></dfn> = <<custom-property-name>> <<css-type>>? [ : <<declaration-value>> ]?
+<dfn><<css-type>></dfn> = <<syntax-component>> | <<type()>>
+<dfn>&lt;type()></dfn> = type( <<syntax>> )
 </pre>
 
 The name of the resulting [=custom function=] is given by the <<function-name>>,
-the [=function parameters=] are optionally given by <<parameter-list>>,
-the [=function dependencies=] are optionally given by <<dependency-list>>,
-and the [=return type=] is optionally given by the <<type>> following the "returns" keyword.
+the [=function parameters=] are optionally given by <<function-parameter-list>>,
+the [=function dependencies=] are optionally given by <<function-dependency-list>>,
+and the [=return type=] is optionally given by the <<css-type>> following the "returns" keyword.
 
 <div class='example'>
-	If the <<type>> of a [=function parameter=],
+	If the <<css-type>> of a [=function parameter=],
 	[=function dependency=],
 	or [=custom function=] return value
 	can be described by a single <<syntax-component>>,
@@ -151,9 +152,9 @@ and rules defined later win within the same layer.
 
 The <<function-name>> of a ''@function'' rule is a [=tree-scoped name=].
 
-If the <<parameter-list>>
+If the <<function-parameter-list>>
 contains the same <<custom-property-name>> more than once,
-or if the <<dependency-list>>
+or if the <<function-dependency-list>>
 contains the same <<custom-property-name>> more than once,
 then the ''@function'' rule is invalid.
 
@@ -213,8 +214,8 @@ A <dfn><<dashed-function>></dfn> is a [=functional notation=]
 whose function name starts with two dashes (U+002D HYPHEN-MINUS).
 Its syntax is:
 
-<pre class="prod def" nohighlight>
-	--*() = --*( <<declaration-value>># )
+<pre class="prod informative" nohighlight>
+	--*( <<declaration-value>># )
 </pre>
 
 Issue: Mention semicolon upgrades.
@@ -231,8 +232,8 @@ When a value is being computed,
 substitution of ''var()'', ''env()'' and ''attr()''
 must take place <em>before</em> <<dashed-function>> substitution.
 
-	Note: This means arguments passed to a custom function
-		never contain ''var()'', or similar functions.
+Note: This means arguments passed to a custom function
+never contain ''var()'', or similar functions.
 
 A ''var()'' function within a [=local variable=],
 or within the ''@function/result'' descriptor,