How to add full width divider images in content

Hi,

I am creating a WordPress theme based on BootstrapWP (https://320press.com/wpbs/). I am struggling with adding full width divider images and wondering if anyone could give me any pointers.

I’m having issues as everything is wrapped in the container and is therefore cut on each side.

In case I’m not making any sense, the end result that I am trying to create is this: https://www.wearecampfire.co.uk/client/workingrite-prebuild/

Any assistance would be greatly appreciated!

Thanks in advance.