A smart toggle-able dark mode theme for Google Classroom.
Dark Mode will be enabled between 6PM and 6AM.
To toggle darkmode at any time, click on the new Sun/Moon icon you see at the top of the google classroom page, next to your profile icon and "join a class" button.
NB. If you are comfortable with slightly modifying the code, to change this timing, head down towards line 260, and change the 18 and 6 you see to your respective hours
