GP Containers are not responsive

Hi, I'm having troubles with GP Containers.
They work pretty well on desktop devices, but on mobile everything is broken.

If I understand well the GP Containers, I can change all of its properties by switching Desktop/Tablet/Mobile, and each will remain independent even if they have different values on every property.

The thing is... it doesn't work. I keep changing and uploading my changes over and over, they look good if I choose "Preview view (mobile)" on the same WordPress editor, but when I look at them in another browser or in other's phone, my site is still broken. (I've done all the cache cleaning).

My site is https://eltiotech.com

Thanks.