Different looking toolbars and missing shadows with GTK3

[Staffan Gimåker <staffan gimaker se>]

Hi,

I just ported my application to GTK3 (gtkmm-3.0 more specifically). The
process went smoothly, but a few minor questions relating to the looks
of my application in GTK3 remains. I'm using the Adwaita theme (the
GNOME default I believe) and all my GUIs are made in Glade and loaded
through GtkBuilder. So:

1. The toolbar in my app looks different from the ones in e.g. Nautilus
and Evolution. The toolbar in Nautilus has a nice dark, gradient look,
whereas my toolbar does not; no gradient, a different button look etc.
Question: how come and what do I do to fix it?

2. I get no "shadows" (as in GtkShadowType) on any of my widgets
(toolbar excepted, it has an out-shadow), no matter what I try. Is this
intentional, a Glade/GtkBuilder bug or a stupid mistake on my part?
Other apps such as Evolution still has shadows so I'm guessing its one
of the latter two.

I'm guessing both my problems are some glaring omission on my part,
hopefully someone can point me in the right direction :D

Thanks!

/Staffan