Wolfram Technology Guide: Symbolic Interface Construction  previous | next 
Arrange Controls Using Typesetting Constructs
Mathematica lets you use every aspect of its rich typesetting system when you lay out controls.
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Panel[Grid[Table[Button[x^i + y^j], {i, 10}, {j, 6}], 

  Background -> {{{LightRed, LightYellow}}}]]
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