Note: this commit features extensive changes to the behavior of the
sidebar and how it's impelmented. As a result, the animation bug in the right
and left sidebars was fixed.

Note: The header of the card was updated to include an icon for the
module term and the footer was updated to include the percentage of
completion.

Description: Hover transitions are much smoother now for buttons. Note that
this transition only applied to the background of the button.

Note: This is just an experimental commit to play around with this feature.
This may have to be adjusted in the case that cards contain other links in the
future.