In the Scene Builder I can choose for preview a JavaFX Theme called "Gluon Mobile". How can I set the Gluon Mobile theme for my desktop app by code?

What I have:

setUserAgentStylesheet(STYLESHEET_CASPIAN); // default theme

What I want:

setUserAgentStylesheet("SOME_GLUON_THEME_PATH");

OBS: I don't want a Gluon Project for Desktop/Mobile, I just want to use the Gluon Theme.

Sorry for the dumb question, but I did some research and didn't find out how.