Constraining the height of widgets and their contents

Hello,
This may be a more general pout regards design and css but I am trying to have all the widgets showing on the page as the same height no matter what the content. i.e. the box defines the size of the content and not eh other way about. I am sure that there is a line of code I should be adding. I have tried max min height etc with mixed results.
The widgets are contained within a row using the site origin page builder.

Just interested to know if anyone has an insight or recommendation at all.

Many thanks

anthonyod