[indexes] Rearrange sections, separate properties and descriptors. #13498

Author: tabatkins

indexes/Overview.bs

@@ -18,7 +18,7 @@ Introduction {#intro}
 
 This is a non-normative document.
 It lists every term defined in CSS,
-as long as it's marked up correctly for the spec generator.
+as long as it's marked up correctly for <a href="https://speced.github.io/bikeshed">Bikeshed</a>.
 It is intended as a reference document for authors, implementors, and spec authors,
 to aid in finding the definition for a term
 hidden somewhere in the haystack of CSS specs.
@@ -27,20 +27,32 @@ There are some things missing,
 and there are several mistakes,
 either from use of legacy markup patterns that haven't been updated yet,
 or the dfn-type-autodetector misfiring.
-These will be cleaned up over time.
+These will be cleaned up over time;
+feel free to report them so we can fix them,
+or submit a PR yourself.
 
 Issue: A notable absence at the moment is a list of all the "dfn" type definitions--
 the ordinary words and phrases given meaning in CSS.
-This will show up shortly,
+This will show up at some point,
 as soon as I add a mechanism to limit the index generation
 to specs from a particular group.
 (Right now you have to either list every spec you want explicitly,
 or draw from all specs.)
 
-Properties and Descriptors {#properties}
+At-Rules {#at-rules}
+====================
+
+<index type=at-rule></index>
+
+At-Rule Descriptors {#descriptors}
+==================================
+
+<index type=descriptor></index>
+
+Properties {#properties}
 ========================
 
-<index type="property, descriptor"></index>
+<index type=property></index>
 
 Property/Descriptor Values {#values}
 ====================================
@@ -57,11 +69,6 @@ Functions {#functions}
 
 <index type=function></index>
 
-At-Rules {#at-rules}
-====================
-
-<index type=at-rule></index>
-
 Selectors {#selectors}
 ======================