Open your Calendar app or website
Go to Settings or Preferences
Look for Appearance, Theme, or Display options
Select Dark Mode or Dark Theme
If no calendar setting exists, enable dark mode in your laptop’s system settings
On Windows, open Settings > Personalization > Colors > Choose your mode > Dark
On Mac, open System Settings > Appearance > Dark
Refresh or restart the Calendar app if needed
Check if your browser has a dark mode setting if you use Calendar in a browser
Update the Calendar app if dark mode is not available
Use a dark mode browser extension if the calendar still stays light