Question about setting up the Demo Electronics menu

I figured out the import.
But I still couldn’t understand how you made the sofa go beyond the boundaries of the pop-up menu. I just wanted to recreate it, but not with a sofa, but with another object, for example. But I didn’t succeed.

Hello!
I found a place to replace the image.
But I noticed that if we change the text in the menu, then depending on the text, and it can be larger or smaller, this affects the size of the text fields.
And then a shift occurs and the background may not look like yours.
I seem to have more or less figured it out. But I tried to do a test for myself and in the right column, where you have the text above the sofa, I tried to put a small banner instead of the text for the test.
Which led to the incorrect display of the background)) The background is simply cut off beyond the scope of the opening menu window.
I couldn’t figure out how to fix this.
Or for example, if I want to use 3 columns for text instead of four, there is also a problem))
Here I have attached a screenshot for you, where I left 4 columns with text.
But if, for example, I remove the text from the last column, then the background and the markup shift.