data:extend(
    {
        {
            type = "sprite",
            name = "sprite_zout",
            filename = "__some-zoom__/graphics/but-zout.png",
            width = 22,
            height = 30,
        },
        {
            type = "sprite",
            name = "sprite_zin",
            filename = "__some-zoom__/graphics/but-zin.png",
            width = 22,
            height = 30,
        },
    }
)

--------------------------------------------------------------------------------------
local default_gui = data.raw["gui-style"].default

default_gui.zoom_flow_style =
{
    type="horizontal_flow_style",
    parent="horizontal_flow",

    top_padding = 0,
    bottom_padding = 0,
    left_padding = 0,
    right_padding = 0,

    horizontal_spacing = 0,
    vertical_spacing = 0,
    resize_row_to_width = true,
    resize_to_row_height = false,
    max_on_row = 1,

    graphical_set = { type = "none" },
}

default_gui.zoom_sprite_style =
{
    type="button_style",
    parent="button",
    top_padding = 0,
    right_padding = 0,
    bottom_padding = 0,
    left_padding = 0,
    width = 28,
    height = 36,
    scalable = false,
}