Size expressions for bordered boxes

The x-Size and y-Size properties specify the inner size of the box; if we specify a box to be 3cm wide and have a 1mm thick border on all sides, for example, the box's outer bounds will appear to be 3.2cm wide. This conforms to the CSS specification.

You can define the outer bounds of a box instead:

• Determine the x-Size and y-Size values by subtracting the width of the borders from the desired height and width. For example, if you want a box to be 3cm wide on the outside while having 1mm borders on all sides, calculate the width to be 3cm-2mm=2.8cm wide.
• If you want a box to have the same size as its parent, however, set both the x-Size and y-Size properties to the value max. You do not have to subtract the borders, since the system automatically adjusts the value of max in cases where the box has borders. For example, if the box has a 1mm border and is contained in a box that is 3cm high and wide, the outer bounds of the contained box will also be 3cm.