DWV design. New bathroom on slab. one vent pipe?

Thank you in advance for all observations and critiques.
After reading this forum, I’ve decided to post my DWV design. This is a small bathroom over a concrete slab. The plumbing under shower pan is 2’’ pipe, followed by p-trap and WYE, tilted 45 deg straight to the wall and up thru the roof. Everything downstream is 3â€dia. and connected to main drain. (This is a single story house in California, if that makes any difference). My biggest concern is: one vent for two fixtures - Is this a big no-no or I have to one way or another vent the toilet independently?
Thank you
McBV




view from under the slab:

where is the sink?

Hi,
The sink is combined with the toilet (the brand is Caroma). It sits on the top of the tank. This is a small 80”x 80” bathroom – I could not find a room for a standalone sink.
Thank you.
McBV