Stilo It is a clean, simple and stylish GTK theme package for the GNOME desktop. It contains 2 main themes, Stilo and Stiloetto, each of which has a light and shade change. The GNOME Shell theme is also available.
Both Stilo and Stiloetto use gray and blue. The difference is that Stilo is completely flat and square, while Stiloetto uses a slight gradient for the title bar and slightly rounded corners for the application window and elements like buttons and drop-down menus.
These are the Stilo and Stiloetto GTK themes (each version has light and dark versions):
See also: Install GNOME Themes-Script to Install Over 40 Popular Gtk Themes
Themes are still under development, so their appearance may change. They need very new GTK 3.24.6+ and GNOME Shell 3.30+ (supports Fedora 29+ and Ubuntu 19.04). Themes may work in older versions, but the creators cannot guarantee their appearance or intent.
The package includes both light and dark versions of Stilo and Stiloetto GTK 2 and 3 themes, as well as GNOME Shell themes.
To use Stilo, you must build it from source code. Dependencies (for Debian / Ubuntu / Linux Mint, Arch / Manjaro / Antergos, openSUSE and Fedora) and exact installation instructions can be found at Theme project page.
If you are not familiar with how to change GTK and GNOME Shell themes, see This one release.
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