Google Calendar has received a redesign and now features a dark mode option. The update includes a "refreshed user interface" with modernized buttons, dialog boxes, and sidebars. Users can toggle between light and dark modes by clicking the settings icon in the top right corner of the Google Calendar interface. This visual refresh also applies to the task list view.

Source: https://www.theverge.com/2024/10/24/24278419/google-calendar-web-dark-mode