[css-values-5] Whoops, left this bit out of the previous commit by accident. #11634

Author: tabatkins

css-values-5/Overview.bs

@@ -2126,12 +2126,10 @@ Argument Ranges</h4>
 	is large enough to become infinite in the user agent,
 	the result is NaN.
 
-	If C is negative and non-zero,
-	the result is NaN.
 	If C is infinite,
 	the result is A.
 
-	If C is zero,
+	If C is negative, zero,
 	or positive but close enough to zero
 	that the range for the step multiplier
 	(the <code>N</code> mentioned in the argument's definition)