Formatting every other row in a style different from default is supposed to help following rows (in a printout e.g.). This was the reason to use the so-called listing paper already decades ago when matrix printers were the state of the art where you couldn’t get actual grey, not to speak of colors.
You can “emulate” that with te help of conditional formatting in mode ‘Formula is’ making the cell style to overlay depend on whether or not the row number is odd.
Mostly the second style is set to a slightly darker color (than default’s whit), say light grey or light lime.
Using a shadow instead is, of course, possible, but will irritate more than help, imo.
Look into this attachment to experience what I mean.
Well, you may aim at a different look. Edit your question to make it more clear.
(Generally: Tell your actual and final intentions when posting a question.)
Editing:
Based on te additional information: If you want to modify the listing-paper-style based on different colors for some columns, you need to define a conditionally varied (darkened e.g.) style for every such column, and to diversify the CF. Nice complication I would assume. I would prefer common light grey for every other row.
There are no “relative colors” (changing brightness) - and you cannot even simulate it by user code (macros) because conditionally assigned cell styles aren’t assigned to the cells but only overlaid to their areas in the cell grid of the current view.
Edit2: New attachment
Here it is.