Flex container helps to make columns to even heights. Below is an examples for the implementation on panels, wells and thumbnails

Note: You need to use flex-col and flex-grow to make footer / action buttons to align at the bottom. These classes are best to adjust the body-row of a 3 rowed element.
EXAMPLE
Title flex-col
Content here -- div with .flex-grow
Title
Content here -- div with no footer
Duis pharetra varius quam sit amet vulputate.
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Duis pharetra varius quam sit amet vulputate. Quisque mauris augue, molestie tincidunt condimentum vitae, gravida a libero. Aenean sit amet felis dolor, in sagittis nisi.

Related classes: