Enable Styling of Elements or Overrides of Existing CSS

[rjray]

We have found that some elements of the package have hard-coded CSS without the benefit of encompassing class-names. This makes it very difficult to override any part of the CSS. For example, the marker components such as TodayMarker all render the vertical line as black, which is essentially invisible in a dark-mode CSS environment.

Describe the solution you'd like

All elements that a user might use (those exported from the package) should have their CSS defined in terms of named classes. This will allow users to augment the pre-defined CSS with values for the application being developed.

Describe alternatives you've considered

I have considered creating elaborate CSS selectors to alter the TodayMarker background-color, but the lack of definitive class-names makes it very difficult to target the correct div element.