[css-grid] Use class=switch in 'Initialize Track Sizes' for readability.

--HG--
extra : rebase_source : aa835726f8ed49dc083f168449e6e1d53195a672

Author: tabatkins

css-grid/Overview.bs

@@ -1479,6 +1479,7 @@ Sizing Auto-generated Rows and Columns: the 'grid-auto-rows' and 'grid-auto-colu
 
 	<pre class='propdef'>
 	Name: grid-auto-flow
+	Value: [ row | column ] || [ dense | stack ]
 	Value: [ row | column ] && dense?  |   stack && [ row | column ]?
 	Initial: row
 	Applies to: <a>grid containers</a>
@@ -2635,7 +2636,7 @@ Initialize Track Sizes</h3>
 	For each track,
 	if the track's <a>min track sizing function</a> is:
 
-	<dl>
+	<dl class=switch>
 		<dt>A <a>fixed sizing function</a>
 		<dd>
 			Resolve to an absolute length and use that size as the track’s initial <a>base size</a>.
@@ -2652,7 +2653,7 @@ Initialize Track Sizes</h3>
 	For each track,
 	if the track's <a>max track sizing function</a> is:
 
-	<dl>
+	<dl class=switch>
 		<dt>A <a>fixed sizing function</a>
 		<dd>
 			Resolve to an absolute length and use that size as the track’s initial <a>growth limit</a>.