Change content padding

Hi guys,

Having a problem with a new page I have created.

https://workingsheepdogtraining.com/overview-of-the-4-systems-of-arm-signals/.

I don't seem to be able to adjust the padding of the content - it has no padding as you can see. I have tried various css options but nothing seems to work. Not sure why it doesn't have any padding, as I have padding set I think in the customizer options.