[css-grid] Minor wording tweaks / capitalization.

Author: fantasai

css-align/Overview.bs

@@ -1599,7 +1599,7 @@ and its 'row-gap' and 'column-gap' sub-properties,
 provide this functionality for some layout modes.
 
 <h3 id='column-row-gap'>
-The 'column-gap', 'row-gap', And 'gap' Properties</h3>
+The 'column-gap', 'row-gap', and 'gap' Properties</h3>
 
 	<pre class='propdef'>
 	Name: row-gap, column-gap

css-grid/Overview.bs

@@ -3251,7 +3251,7 @@ Gutters: the 'row-gap', 'column-gap', and 'gap' properties</h3>
 	Their syntax is defined in [[css-align-3#gap]].
 
 	The effect of these properties 
-	is as though the affected <a>grid lines</a> acquired width:
+	is as though the affected <a>grid lines</a> acquired thickness:
 	the <a>grid track</a> between two <a>grid lines</a>
 	is the space between the <a>gutters</a> that represent them.
 	For the purpose of [[#algo-track-sizing|track sizing]],