[css-fonts-4] font-variation-settings should clamp to the closest value supported

by the font.

#517

Author: litherum

css-fonts-4/Overview.bs

@@ -1180,10 +1180,13 @@ at least as dark as its predecessor. Only values between 1 - 999 are valid, and
 	<a href="https://www.microsoft.com/typography/otspec/fvar.htm">name rules</a>
 	defined in the OpenType specification.
 
-	Axis values not present in the font, or axis values greater or less than the range supported by the font, are ignored and therefore have no effect; a user agent must
+	Axis values not present in the font are ignored and therefore have no effect; a user agent must
 	not attempt to synthesize fallback behavior based on these axis tags. Other axis values
 	within the same CSS 'font-variation-settings' statement are not ignored.
 
+	Axis values greater or less than the range supported by the font are clamped to the closest value supported by
+	the font.
+
 	Values are allowed to be fractional or negative.
 
 	If the same axis name appears twice, the second one supercedes the first.