fix(Datepicker): update 'today' cell background color in dark-v2 them…

…e to increase contrast (#18461)

* date picker today

* changelog

packages/fluentui/CHANGELOG.md

@@ -41,6 +41,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Fix RTL version of `NumberListIcon` @notandrew ([#18310](https://github.com/microsoft/fluentui/pull/18310))
 - Fix `ChatMessage` badge-bar conflict with focus-border @Hirse ([#18303](https://github.com/microsoft/fluentui/pull/18303))
 - Fix `Dropdown` to pass all positioning props to its inner `Popper` @yuanboxue-amber ([#18457](https://github.com/microsoft/fluentui/pull/18457))
+- Update `Datepicker` today cell background color in dark-v2 theme to increase contrast @yuanboxue-amber ([#18461](https://github.com/microsoft/fluentui/pull/18461))
 
 ### Features
 - Add Default Border Transparent and Default Foreground9 colors @notandrew ([#17906](https://github.com/microsoft/fluentui/pull/17906))

packages/fluentui/react-northstar/src/themes/teams-dark-v2/componentVariables.ts

@@ -1,2 +1,3 @@
 export { chatVariables as Chat } from './components/Chat/chatVariables';
 export { chatMessageVariables as ChatMessage } from './components/Chat/chatMessageVariables';
+export { datepickerCalendarCellButtonVariables as DatepickerCalendarCellButton } from './components/Datepicker/datepickerCalendarCellButtonVariables';

packages/fluentui/react-northstar/src/themes/teams-dark-v2/components/Datepicker/datepickerCalendarCellButtonVariables.ts

@@ -0,0 +1,7 @@
+import { DatepickerVariables } from '../../../teams/components/Datepicker/datepickerVariables';
+
+export const datepickerCalendarCellButtonVariables = (siteVars): Partial<DatepickerVariables> => {
+  return {
+    calendarCellTodayBackgroundColor: siteVars.colorScheme.brand.background,
+  };
+};