The portion of the viewport that is currently visible is called the visual viewport. This can be smaller than the layout viewport, such as when the user has pinched-zoomed. The visual viewport is the visual portion of a screen excluding on-screen keyboards, Areas outside of a pinch-zoom Area, or any other on-screen artifact that doesn't scale with the dimensions of a page....on-screen keyboards, areas outside of a pinch-zoom area, or any other...