Thank very much.
1) Perfect, thanks.
2) This solution is perfect, thanks. On my iPhone11 Pro in landscape version works perfectly, but on portrait mode, the icons with the lens are not visible (see the attached pic in pvt). How to solve this?
Moreover, another question:
now (with me modified CSS) I have 3 portfolio miniatures in desktop version end 3 miniatures in the mobile version.
Could be possible to keep the 3 miniature in the mobile and to have 6 (six) miniature in the desktop version? Unfortunately, 6 is not possible to be chosen in the theme option where the maximum is 4.