Exercise cards are useful in multiple places,
so they should be displayable by an independent
component.

The CSS for making the cards have the correct
width and height is very finicky and took a long
time to get to work. The current styling should
be refactored.

Adjust number of cards per row to the screen's width.

Wrap cards into container to achieve spacing
between the cards.

Let all cards in a row have the height of the tallest
card.