[css-grid-2] Clarify computed value of subgridded axes. w3c#6165

Author: fantasai

css-grid-2/Overview.bs

@@ -2014,7 +2014,7 @@ Flexible Lengths: the ''fr'' unit</h4>
 <h4 id='computed-tracks'>
 Computed Value of a Track Listing</h4>
 
-	The <dfn>computed track list</dfn> of a [=standalone axis=]
+	The <dfn>computed track list</dfn> of a non-''subgrid'' axis
 	is a <a spec=infra>list</a>
 	alternating between [=line name sets=] and [=track sections=],
 	with the first and last items being [=line name sets=].
@@ -2026,14 +2026,17 @@ Computed Value of a Track Listing</h4>
 
 	* a ''minmax()'' functional notation representing a single track's size,
 		with each <<length-percentage>> computed
+		(a <dfn>computed track size</dfn>)
 	* a ''repeat()'' functional notation representing a repeated track list section,
 		with its <<integer>> computed
 		and its <<track-list>> represented as a [=computed track list=]
+		(a <dfn>computed repeat notation</dfn>)
 
-	The [=computed track list=] of a [=subgridded axis=]
+	The [=computed track list=] of a ''subgrid'' axis
 	is the ''subgrid'' keyword followed by
 	a <a spec=infra>list</a> of [=line name sets=]
-	representing each line in that axis.
+	and [=computed repeat notations=]
+	representing the line names specified for that axis.
 
 <!--
 ████████  ████████  ██████   ███████  ██       ██     ██ ████████ ████████