The Fill and Shadow tabs have the same set of parameters that are used to change parameters of object's background and shadow background:

Set the parameters:
Background Color/Foreground Color. Select background and foreground color in the corresponding drop-down palettes. One can specify a custom color by clicking the Other button in the palette.
Background Transparency/Foreground Transparency. Specify background ad foreground transparency value in percents: 100% - background/foreground is transparent, 0% - background/foreground are opaque.
Fill Pattern. Select the required type of background pattern in the drop-down list.
Sample. This area shows background formatted in accordance with the currently selected parameters.
See also: