documentation more consistent

scrbl/rgba.scrbl

@@ -6,7 +6,7 @@
                      racket/string
                      racket/contract))
 
-@title{rgba}
+@title[#:tag "rgba"]{rgba}
 @author[@author+email["Hans Dijkema" "hans@dijkewijk.nl"]]
 
 @defmodule[racket-webview/rgba]
@@ -16,7 +16,7 @@ RGBA color support used by the webview library.
 This module exports a transparent @racket[rgba] structure together with
 predicates and conversion procedures for working with CSS-style color values.
 
-@section{Overview}
+@section[#:tag "rgba-overview"]{Overview}
 
 An @racket[rgba] value represents a color using red, green, blue, and alpha
 components.
@@ -35,7 +35,7 @@ The intended external representation is the CSS form:
 "rgba(r,g,b,a)"
 ]
 
-@section{Predicates}
+@section[#:tag "rgba-predicates"]{Predicates}
 
 @defproc[(rgba/color? [v any/c]) boolean?]{
 
@@ -53,7 +53,7 @@ A valid alpha component is a real number in the range from @racket[0] to
 @racket[1], inclusive.
 }
 
-@section{Structure Type}
+@section[#:tag "rgba-structure-type"]{Structure Type}
 
 @defstruct*[rgba ([r rgba/color?]
                   [g rgba/color?]
@@ -68,7 +68,7 @@ components. The field @racket[a] is the alpha component.
 The structure is transparent.
 }
 
-@section{Conversion}
+@section[#:tag "rgba-conversion"]{Conversion}
 
 @defproc[(rgba->string [c rgba?]) string?]{