After you apply a style, you can
override any of its settings. If you decide you like the changes,
you can redefine the style to retain the new formatting.
Note: For cell styles, changes to only those attributes
that are part of the cell style will enable the Redefine Style command.
For example, if the cell style includes a red fill and you override
a cell to use a blue fill, you can redefine the style based on that
cell. But if you change an attribute that is ignored in the cell
style, you can’t redefine the style with that attribute.