Step 4.
Now duplicate the GridItem by copying and pasting so that you now have 2 identical GridItems.
you should now see the same image twice with a blue border around each grid as shown below:
And if we duplicate a GridItem again and preview we get:
So this is using the default GridPlus settings which is set to 250px so that if when a grid item width is less than 250px, the Grid will stack.