I would like to be able to specify a special theme designed for mobile devices, regardless of the chosen default theme.
We have 2 themes "Blue V2" and "Blue mobile"
It turns out if the user visits a web browser from a computer, it opens a standard design theme ( "Blue V2").
If a user enters on a mobile device or tablet that site it opens in the theme is specified for mobile devices ( "Blue mobile").
Excuse me if this is where it was, I could not find.