How to make background-images stretch outside the site?

Question

Uninterruptable power source

The layout has blocks that go beyond the site, similar to infinite ears. The background of these blocks is a picture. How to implement this in css?
The site where you need to implement this https://rimidbit.github.io/retroclimate/index.html
Please explain using the example of the first block under the heading "CLIMATE EQUIPMENT
FOR YOUR COMFORT"