Fix CSSMathSum args type (mdn#43694)

* Fix CSSMathSum args type

https://drafts.css-houdini.org/css-typed-om/#dom-cssmathsum-cssmathsum

sum rather than product

* Update parameter description for CSSMathSum (mdn#43695)

* Update index.md

* Update index.md

Author: estelle

files/en-us/web/api/cssmathmax/cssmathmax/index.md

@@ -22,8 +22,7 @@ new CSSMathMax(args)
 ### Parameters
 
 - `args`
-  - : A list of values for the {{domxref('CSSMathProduct')}} object to be either a double
-    integer or a {{domxref('CSSNumericValue')}}.
+  - : A list of numbers or {{domxref("CSSNumericValue")}} objects.
 
 ### Exceptions
 

files/en-us/web/api/cssmathmin/cssmathmin/index.md

@@ -23,8 +23,7 @@ new CSSMathMin(args)
 ### Parameters
 
 - `args`
-  - : A list of values for the {{domxref('CSSMathProduct')}} object to be either a double
-    integer or a {{domxref('CSSNumericValue')}}.
+  - : A list of numbers or {{domxref("CSSNumericValue")}} objects.
 
 ### Exceptions