Cell Themes
Themes can be
applied to each Cell that you select. Themes can also be applied
to the Page Layout for the entire spreadsheet..
Try it: Apply a Theme
Go to
Page Layout -> Themes
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What Do You See? Microsoft Excel has many Built-In Themes
that format the Colors, Fonts and Effects. You can see the different
formatting in Live Preview as you run your mouse over the gallery of
Themes.
Keep going...