[css-variables] typo

Author: tabatkins

css-variables/Overview.html

@@ -765,7 +765,7 @@ <h4 id=serializing-custom-props><span class=secno>4.1.1. </span>
   <p> Custom property names must be serialized with the casing as provided by
    the author.
 
-  <p class=note> Ordinarily, property name are restricted to the ASCII range
+  <p class=note> Ordinarily, property names are restricted to the ASCII range
    and are case-insensitive, so implementations typically serialize the name
    lowercased.
 

css-variables/Overview.src.html

@@ -562,7 +562,7 @@ <h4 id='serializing-custom-props'>
 	Custom property names must be serialized with the casing as provided by the author.
 
 	<p class='note'>
-		Ordinarily, property name are restricted to the ASCII range and are case-insensitive,
+		Ordinarily, property names are restricted to the ASCII range and are case-insensitive,
 		so implementations typically serialize the name lowercased.
 
 <h3 id='the-cssvariablesdeclaration-interface'>