How to scroll progressively a game object?

I am developing a game with Unity which has a main menu to allow the user select game mode. In this screenshot you can see an example:

My problem is the following:

I need to create a scroll in which user can put his finger on point 1 and swipe to point 2. On the one hand, while this action is happening the element 2 increase its opacity and its position change progressively to the center. On the other hand, while this action is happening the element 1 decrease its opacity and its position change progressively to the left part of the screen.

Extra information:

The elements are sprites with colliders to detect the selection of the player.

What would you suggest me to do? Have you got any code to solve this? Any other suggestion?