Hi Alberto,
I made some troubleshooting. First, I have duplicate 1 grid. You can see Grid 3. I have choose another skin on this GRID 3. The issue persist. This means the issue is not coming from custom skin.
On frontend, weirdly enough I saw the height of the grid is set to 0. Then I found out it is because of 250px left and right padding set on GRID SETTINGS TAB > PADDINGS. Note on mobile, the screen is narrow, when you put 250px padding on left and right, there’s nothing left for the content area. So I remove it instead. Visualcluetext4 grid is now showing on mobile. It is still fullwidth though. I have set this GRID LAYOUT to BOXED so it will follow the width of its container which is the SECTION > ROW width on Content editor.
If you don’t want the grid to show fullwidth, no need to add padding on Essential grid. See it here: https://fragmentsoflife.net/gallery2/
On section 1 > Inspect ROW.
I have set Inner Container Option to OFF.
Set maximum width for the ROW. Currently, I have set it to 1000px. Adjust accordingly.
Please repeat the process on other Grids and other ROW.
Hope this helps.