Shading every other row but not changing background color

Is there a way to shade every other row but maintain background colors only adjusting the darkness of it?
ISEVEN(ROW()) is where I was thinking to start for conditional formatting but cant figure out where to from there.

Edit: So I think what I would like to be able to do is change the alpha of background colors of cells. So if a column is set with a particular background color each cell still varies a different darkness of that color.

To be honest, I don’t understand how you want your rows to look like. Shading has a special meaning, which would make cells look like this:

image description

Is it that what you mean?


> only adjusting the darkness of it

What is the darkness of cell other than to apply a darker background (which you don’t want to change)? Confusing …


> ... every other row

Missing …than, …every other row than which row?


> ISEVEN(ROW()) is where I was thinking to start

This would make sense if you want odd rows to look like cell style MyOddRowCells and even rows look like cell sytle MyEvenRowCells

Added an edit. But still not sure I am describing it correctly.

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.

Cool thank you. Sorry for the run around getting the question described… in retrospect should have just made something look like what I wanted.

Don’t worry. With hindight I see: I simply hadn’t read your question thoroughly enough.