For styling, if your interface is focused on tables and forms, as opposed to bespoke components, you might try a minimalist CSS library like Pico or Milligram.

For styling, if your interface is focused on tables and forms, as opposed to bespoke components, you might try a minimalist CSS library like Pico or Milligram. As for functionality, if you're "just" doing some calculations and presenting it like a spreadsheet, you probably don't need a framework. Some plain Javascript onChange event listeners for your various input fields might be all you need.