You will need to enter your administrative password for sudo.
As soon as you're finished, you should also install gtk-chtheme by typing sudo port install gtk-chtheme. You may also have to enter your administrative password here. You can now proceed to select the theme you will be using in newly-launched GTK apps by typing gtk-chtheme in your terminal. A graphical application will launch that provides live previews of your selected theme. When you find one you like, just press OK.
With a theme chosen, every GTK2 application launched will look beautiful.
note : OSX 10.7 higher first install Xcode on App Store (free)
download Smooth UI Inkscape GTK OSX - goo.gl/MHaJca
GTK Smooth themes :
1. Extract smooth_gtk-osx.tar.gz to directory /opt/local/share/themes/
2. Open terminal type command
3. Select theme smooth_gtk-osx
4. Enjoy look beautiful GTK Apps on OS X
UI Inkscape icons replace
1. Click right Inkscape.app on folder Application
2. Replace icons.svg on directory /Contents/Resources/icons/
3. Enjoy drawing
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