background picture for widget layout | Community Development | Sandbox ConnAct

You can set a background image for a space. 

For every space we have a unique class name, you just have to get the class name of the space you want to add background image to and add it to css overrides with the customizations you want, for example in your case you want to add a background image so for that the code will be:

.class-name{
 background-image: url("https://images.pexels.com/photos/34950/pexels-photo.jpg?auto=compress&cs=tinysrgb&h=350");
}

Does this help achieve your goals?