Best way to include multiple game themes into the game each with different game objects?

Hi, I am fairly new to unity and I have a question about incorporating multiple different themes to my game. My game is a 2d game that has a player and objects are spawned in that the player has to catch and add to their score. Each theme will have different game objects and colour scheme, but the concept/scripts remain the same. I’ve worked on the main/default theme with its specific objects and scripts but was just wondering what’s the best way to set up these multiple game themes?
(To get a reference to what I mean would be like doodle jump how the game has different themes you can choose etc original/pirate, but the game concept is the same.) thank you

You can define theme scriptable objects wit ha bunch of variables, colors and other parameters. Then, everywhere you have some UI, you can have sepcial theme components that tune specific visualization parameters according to the referenced theme asset. One global manager can also get all theming components in the scene and trigger switching to the other theme asset…