You have different layout options when creating a grid. Either specify an exact width for each grid item or set the number of columns you want to have for your grid.
Different layout options can be set for desktop, tablet and mobile with the exact breakpoints you need as defined on the settings page.
Demo – Fixed Width
This grid is set to have items of 150 pixels wide on desktop but switch to 100 pixels wide on tablet. For mobile we’ve set it to switch to 2 columns instead of fixed width.
Demo – Number of Columns
This grid is set to have 4 columns on desktop, 3 on tablet and 1 column on mobile.