Hi Bartolo,

as Star Gold head to of OS‘s Senator Lounges. They‘ll provide what you need (food, shower) although not terribly exciting...
you can find them in the T3 Schengen and non-Schengen areas. In the rare case that your onward flight leaves from the D non-Schengen Gates in Terminal 1 there is a decent enough OS
Lounge after Passport Control (but before Security, which happens at each gate). Safe travels.