[css-values-3] Refer to the type vs syntax defs correctly in the Angles section.

Author: tabatkins

css-values/Overview.bs

@@ -1086,9 +1086,9 @@ Other Quantities</h2>
 <h3 id="angles">
 Angle Units: the <<angle>> type and ''deg'', ''grad'', ''rad'', ''turn'' units</h3>
 
-	Angle values are <a>dimensions</a> denoted by <dfn id="angle-value">&lt;angle></dfn>.
+	Angle values are <<dimension>>s denoted by <dfn id="angle-value">&lt;angle></dfn>.
 	However, for zero angles the unit identifier is optional
-	(i.e. can be syntactically represented as the <<number>> ''0'').
+	(i.e. can be syntactically represented as the <a>number</a> ''0'').
 	The angle unit identifiers are:
 
 	<dl export>