Bootstrap 4 cards - Can't get them responsive

Welcome to the forums, @steambc.

That would certainly help - either that or a link to a live page where we can see the issue.

When you post code on the forums, you need to format it so it will display correctly. You can highlight your code, then use the </> button in the editor window, or you can place three backticks ``` (top left key on US/UK keyboards) on a line above your code, and three on a line below your code. I find this approach easier, but unfortunately some European and other keyboards don’t have that character.

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