I'm totally new at this. I want to make a 3 column image element with just a bit of padding between the images. It shows up perfectly everywhere but gmail web. It shows the three images right next to each other.

You can see my code here:

https://codepen.io/marijke34/pen/oNgKdGE

And how it shows ups in checklist: https://litmus.com/pub/1b3e31c

Could anyone explain what I'm missing here?