What should I do to make the promotion work for all variants?

The discount in Sale only works on the base price.
I would like it to work on variants as well, i.e. I would calculate the discount from the final price.

How do I do it?

I made screenshots that will illustrate my problem well.

As you can see Sale -10% is set
price reduction from default variant is -7.08€
When you select another variant Sale -7.08€ is still calculated, which is -10% from the price of 70.73€
What do I need to do to make the price calculated from the final value after selecting all variants

What LiteCart version are you on? Last I remember is this change has been made already, and there is user feedback to go back to the not reducing prices for options again.

My version is 2.5.4

Different users have different expectations.

Our product cards are very extensive so as not to create over 100 variants of the same product in the form of separate offers (mainly different colors and package sizes).

I don't know how complicated it will be for you, but you can create options in the settings that will switch between these two types of price reduction calculations in Sale.

Litecart will become more universal. The user will decide what fits his strategy.

I just set up a new store on version 2.61 to check it and the discount from Sale is still counted from the basic price but in different way

In the example, the base price is PLN 70 x 10% = 7 PLN
The most expensive variant in this offer is priced at 110.
With SALE 10%, the store corrected its initial price (from 110 it made 106) to display the correct result, i.e. 110 - 10% = 99

It turns out that Litecart manipulates the starting prices to show the correct result.
If these manipulations were not visible to customers, everything would be fine

The result is correct, but the information about the 10% discount is not consistent with the prices

As you can see litecart's forced price 106 PLN - 10% = 95.4 PLN
When I turn off SALE, the base price of this variant is correct again, i.e. 110

It's hard for me to explain this, I'll put a link to the offer so you can see what I'm writing about
The variants have set prices of PLN 70, 80, 90, 110

https://szukamfachowca.eu/pl/remonty-budynkow-c-9/ocieplanie-piana-pur-pila-budujto-p-1

Sorry for store language, its only polish for now

Can you show your options configurations?

Sure
I translated the page using Chrome to make it easier to understand

Did you check if the demo has the same behavior?
https://demo.litecart.net/

The problem is when the variants are priced differently.

Yes, I checked the demo. There, the ducks have the same price of $20. Unfortunately, the demo does not provide any new information.

Sorry, is your problem is reproducable with the demo 2.6.2, or it is not reproducable?