1. Create option in Agency company settings for agency admins/owners to turn on or off that is: "Allow all users to toggle light / dark mode individually." That way, this option is off by default, giving all GHL agencies time to write code for whichever mode they've not got code for.
  2. Turn current Custom CSS box in Agency company settings into "Custom CSS for light mode" ... and then "add Custom CSS for dark mode" right below it.
  3. Provide light/dark mode toggle for all users under "My Profile" or in upper right hand corner, similar to the light/dark mode toggle used in Community feature. Only make available if option in point #1 (above) is turned on by agency admin/owner.