You can change the formatting attributes of layout objects, layout parts, and the layout background to customize layouts. You can fill objects, parts, and the background with a solid color, a color gradient, or an image. In addition, you can specify that objects and parts display a border and then customize the color and line style of the border.
The layout background, layout parts, and objects are layered on a layout. If you set the fill to transparent for objects in the foreground, then objects, parts, or the layout background will show through. For example, if you change the fill of the layout background but don’t see the result of your changes, make the fill of the layout parts (which are in the foreground) transparent. See Setting the fill, line style, borders, shadows, and padding.