All items regardles if they are text or images, have the following common properties.
Choose Item > Resize to change dimensions of the item. Size of the item includes item background but doesn't include borders.
Line outside the item.
Choose Item > Border to change outline of the item
Interior of the item.
Choose Item > Background to change the background of the item
Space between the outline and the content of the item. Choose Item > Padding to change item padding (space between all 4 sides of the item, or padding specific to one of the edges). The image below has 4 pixel padding, white background and 1 pixel gray border.