Update theme.scss

[atharvnaik1]

1. Implemented changes in theme.scss an respective files for select month, year background in dark mode , day is already correct.
2. Implemented changes in theme.scss and respective files input.react-datepicker-time__input background color from white to dark mode.
3. Updated the time popper for dark theme.
   4.npm run build before start .

[CLAassistant]

All committers have signed the CLA.

[johnsoncherian]

Hi @atharvnaik1 , Thanks for the contribution. Can you sync ur branch with latest develop and check this again. Looks like the style changes are not reflecting on the popup