Hmm ... It's impossible ;-) This RPM doesn't exist on any FTP server

Provides :
application()
application(gtk3-demo.desktop)
application(gtk3-icon-browser.desktop)
application(gtk3-widget-factory.desktop)
gtk3-devel
gtk3-devel(x86-32)
pkgconfig(gail-3.0)
pkgconfig(gdk-3.0)
pkgconfig(gdk-x11-3.0)
pkgconfig(gtk+-3.0)
pkgconfig(gtk+-unix-print-3.0)
pkgconfig(gtk+-x11-3.0)

Requires :

libXi.so.6
pkgconfig(cairo) => 1.14.0
libgobject-2.0.so.0
pkgconfig(pangoft2)
libpthread.so.0
pkgconfig(xcomposite)
libXcomposite.so.1
rtld(GNU_HASH)
libpangocairo-1.0.so.0
libgdk_pixbuf-2.0.so.0
libm.so.6
librt.so.1
pkgconfig(xinerama)
pkgconfig(gtk+-3.0)
libpango-1.0.so.0
libatk-bridge-2.0.so.0
libgailutil-3.so.0
pkgconfig(xdamage)
libXext.so.6
libc.so.6(GLIBC_2.2)
pkgconfig(xext)
/bin/sh
libharfbuzz.so.0
libgmodule-2.0.so.0
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(CompressedFileNames) <= 3.0.4-1
libcairo.so.2
libatk-1.0.so.0
libgdk-3.so.0
libfreetype.so.6
pkgconfig(xrandr)
pkgconfig(gdk-3.0)
libc.so.6
libc.so.6(GLIBC_2.3.4)
pkgconfig(fontconfig)
libXinerama.so.1
pkgconfig(cairo-gobject) => 1.14.0
pkgconfig(pangocairo)
pkgconfig(xfixes)
libXrandr.so.2
libc.so.6(GLIBC_2.4)
libpangoft2-1.0.so.0
pkgconfig(atk-bridge-2.0)
pkgconfig(epoxy) => 1.0
pkgconfig(x11)
pkgconfig(pango)
libgio-2.0.so.0
rpmlib(PayloadIsXz) <= 5.2-1
libXcursor.so.1
libXfixes.so.3
pkgconfig(xi)
gtk3(x86-32) = 3.22.10-4.el7
libgtk-3.so.0
pkgconfig(xcursor)
libXdamage.so.1
pkgconfig(cairo-xlib)
pkgconfig(gio-unix-2.0) => 2.49.4
libc.so.6(GLIBC_2.0)
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
libcairo-gobject.so.2
libm.so.6(GLIBC_2.0)
libX11.so.6
libepoxy.so.0
pkgconfig(gdk-pixbuf-2.0) => 2.30.0
libfontconfig.so.1
libc.so.6(GLIBC_2.1)
/usr/bin/pkg-config
pkgconfig(atk) => 2.15.1
libglib-2.0.so.0
libm.so.6(GLIBC_2.1)
pkgconfig(atk)
pkgconfig(gio-2.0) => 2.49.4

Content of RPM :
/usr/bin/gtk-builder-tool
/usr/bin/gtk-encode-symbolic-svg
/usr/bin/gtk-query-settings
/usr/bin/gtk3-demo
/usr/bin/gtk3-demo-application
/usr/bin/gtk3-icon-browser
/usr/bin/gtk3-widget-factory
/usr/include/gail-3.0
/usr/include/gail-3.0/libgail-util
/usr/include/gail-3.0/libgail-util/gail-util.h
/usr/include/gail-3.0/libgail-util/gailmisc.h
/usr/include/gail-3.0/libgail-util/gailtextutil.h
/usr/include/gtk-3.0
/usr/include/gtk-3.0/gdk
/usr/include/gtk-3.0/gdk/deprecated
/usr/include/gtk-3.0/gdk/deprecated/gdkcolor.h
/usr/include/gtk-3.0/gdk/gdk-autocleanup.h
/usr/include/gtk-3.0/gdk/gdk.h
/usr/include/gtk-3.0/gdk/gdkapplaunchcontext.h
/usr/include/gtk-3.0/gdk/gdkcairo.h
/usr/include/gtk-3.0/gdk/gdkconfig.h
/usr/include/gtk-3.0/gdk/gdkcursor.h
/usr/include/gtk-3.0/gdk/gdkdevice.h
/usr/include/gtk-3.0/gdk/gdkdevicemanager.h
/usr/include/gtk-3.0/gdk/gdkdevicepad.h
/usr/include/gtk-3.0/gdk/gdkdevicetool.h
/usr/include/gtk-3.0/gdk/gdkdisplay.h
/usr/include/gtk-3.0/gdk/gdkdisplaymanager.h
/usr/include/gtk-3.0/gdk/gdkdnd.h
/usr/include/gtk-3.0/gdk/gdkdrawingcontext.h
There is 543 files more in these RPM.