[css-color] Remove the "invalid if sum to zero" wording, #11678

Author: svgeesus

css-color-5/Overview.bs

@@ -219,10 +219,9 @@ Mixing Colors: the ''color-mix()'' Function {#color-mix}
 		(an equal mix of the two colors).
 	3. Otherwise, if <var>p2</var> is omitted, it becomes 100% - <var>p1</var>
 	4. Otherwise, if <var>p1</var> is omitted, it becomes 100% - <var>p2</var>
-	5. If the percentages sum to zero, the function is invalid.
-	6. Otherwise, if both are provided and add up to greater than 100%,
+	5. Otherwise, if both are provided and add up to greater than 100%,
 		they are scaled accordingly so that they add up to 100%.
-	7. Otherwise, if both are provided and add up to less than 100%,
+	6. Otherwise, if both are provided and add up to less than 100%,
 		the sum is saved as an alpha multiplier.
 		They are then scaled accordingly so that they add up to 100%.
 
@@ -231,6 +230,10 @@ Mixing Colors: the ''color-mix()'' Function {#color-mix}
 	and
 	<var>p2</var> becomes <var>p2</var> / (<var>p1</var> + <var>p2</var>).
 
+	<!-- @@ Need to handle the sum to zero case to generate transparent black
+	 	https://github.com/w3c/csswg-drafts/issues/11678#issuecomment-2686226875
+	-->
+
 <wpt>
 	color-mix-percents-01.html
 	color-mix-percents-02.html

css-color-hdr-1/Overview.bs

@@ -447,8 +447,9 @@ Mixing Dynamic Range Limits: the ''dynamic-range-limit-mix()'' function {#dynami
 	parsing.html 
 </wpt>
 
-	If the sum of all percentages is 0%, then the function is invalid.
-
+<!-- @@ handle the case of percentages summing to zero. Distribute equally?
+	https://github.com/w3c/csswg-drafts/issues/11678#issuecomment-2686103826
+-->
 <h3 id="computing-dynamic-range-limit">
 	Computed Value for 'dynamic-range-limit'
 </h3>