How to Install GTK ThemesBefore we go further, here is a quick tutorial on how to install custom GTK themes. (You can skip this part if you know how to do it already.)
First install the “gnome-tweak-tool” by running this command:
sudo apt-get install gnome-tweak-tool
Or if you run Ubuntu Unity, install the “unity-tweak-tool” instead.
sudo apt-get install unity-tweak-tool
Elementary OS users can install “elementary-tweaks.”
sudo add-apt-repository ppa:mpstark/elementary-tweaks-daily sudo apt-get update sudo apt-get install elementary-tweaks
Grab the zip file of your desired GTK theme (from gnome-look or deviant art) and extract. Then move the extracted folder to “/usr/share/themes.”
Note: for your convenience, we have included the link to each shell theme described below so you can get the zip file from there.
Once the theme has been downloaded and extracted to your “/usr/share/themes” directory, open gnome-tweak-tool, unity-tweak-tool or elementary-tweaks to select the theme.
Here are five of the best themes for GTK-based desktop environments.
1. Arc GTK Theme
Arc is a flat GTK theme with subtle transparency effects in some parts of the application window such as those with header bars and the sidebar in Nautilus. It comes in three variants – light, dark and darker (header bar only) – for you to choose from, and it supports GTK3- and GTK2-based environments. I tested this theme on Gnome 3.18 and Pantheon (Elementary OS Freya), and it looked great on both!
Paper is developed with GTK3 (Gnome-based) desktop environments in mind, meaning you can only get the best experience on Gnome 3 and other Gnome Shell-based DEs. Paper theme is inspired by Google’s material design philosophy and makes use of a flat design with minimal shadows for depth. If you want to mimic the look of Android L and M on your desktop, Paper would be a great choice for you.
If you don’t like totally flat themes, you can give Vertex a try. Just like Arc, it has three variants: dark, light and dark headerbars. It supports GTK3 and GTK2 desktop environments such as Budgie, Gnome 3, MATE, Pantheon, Cinnamon and more.
4.Ultra Flat Theme
Ultra Flat theme is a modified version of Numix with no border, flat rounded window buttons and grey selection colour. It was tested in Ubuntu Unity but will work on GTK3 desktop environments.
5. OS X El Capitan
If you want to bring a Mac OS X look and feel to your Linux desktop, this theme is ideal for you! You get the familiar light theming and the trademark OS X window buttons. It’s made for Cinnamon but works on all GTK3 desktops.
Bottom LineWith these five themes, you can make your desktop really shine! Even if you don’t like any of the ones listed above, there are plenty more for you to discover at Gnome-look.org. Let us know your favourite GTK themes in the comments below.