Selection list with sutomatic styling

Hello,

I want to make a data collection sheet, with some of the columns having selectable items. I’ve done this using the Validity tool, and selecting a Cell range from a dedicated Sheet. This works fine.
However I would also like that once a value is selected in a specific cell, that cells background color (formatting) to be updated to be the same as the one from the Cell Range.

This way I can easily tell from the color of the cell, what the value is without having to read it. These cells contain a type/category for the data entered in that row.

I know conditional formatting exists, but that would require me to keep the conditional formatting rules up to date, every time I update the source Cell Range. Not impossible or too difficult, but would rather have something based on a “single source of truth”.