How to create this two row nav? Thank you!

Hi I’ve been exploring ways to create this navigation experience. (see screenshot)
Basically:

  • the main content reflects the combination of row 1 & row 2 (e.g. A1, B3, C2…)
  • for each row, one and only one button should be selected at any time. (e.g. row 1 can’t be “AB” selected, or none letter selected)
  • row 1 and 2 are independent, the don’t affect each other (e.g. switch from A to B in row 1 shouldn’t affect row 2)

Any help is much appreciated!!


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