Background image style does not change between desktop/tablet/phone mode

So, I’m new with blocs, I’ve spent the last days using the trial to test Blocs and I’m pretty impressed with it, with the help and tips found on some YouTube videos I did manage to create a very good-looking website and started to work on responsive features, adjusting some styles between desktop mode and the mobile ones.
My problem is basically on the phone mode, my website is a one page mode, and I setup a couple of full screen sections styled with full screen images with some text on top with a semitransparent darker area for easy text reading, and then I come to realize that the background images don’t keep separate definitions between desk/tablet/phone modes like every other stuff, if I change the image appearance from full screen to center on phone mode and then return to desktop mode, blocs applies that modification to desktop mode also, which is not what I wanted.

The full screen image background with parallax effect looks awesome on desktop, but when I switch to phone mode, it’s awful, because the image gets unrecognizable.

Anyone has a clue on what I might be doing wrong or some tip on how to make this look great on both modes?

Ok so after some digging I found that the best solution is to duplicate the blocs in question and make them visible only on the devices I want, I wish Blocs could address the background style to change from device view natively, duplicating blocs is not a very clean way to do it.
Anyway, by doing this I came across another problem, my site is a One Page site, so I have my navigation menu setup to access targets that I defined by blocs ID, if I duplicate some blocs I cannot use the same ID for the ones meant to display only on mobile, so I ended up with a broken menu.
How to fix this? I really appreciate some help, Thanks.

I have the same problem as @brunocerq.
Blocs I have little time and some things although I have searched this forum can not find solutions.
Someone knows a this problem.
This is the background image of the block may be different for your computer, for tablet and mobile.
Thanks for your help.