Awesome

Adwaita for Steam

A skin to make Steam look more like a native GNOME app

Main Window: Done.
Login: Done
Library: Done
Small Mode: Done.
Chat: Done
Settings: Mostly done.
New Overlay: Mostly done.
New Big Picture: Not done.
Recoloring: Colors can be changed via making a new theme. See colorthemes dir.
Light Themes: Not currently planned, though may now be more feasible with the new UI.

Steam updates may reset theme: While the installer will patch steam files in order to theme the interface, these files may be reset by steam updates. If this happens, you will need to reinstall to repatch them.
Rounded corners: Not all elements can be rounded, use Rounded Window Corners extension or mutter-rounded on GNOME.
Steam website pages (Store/Community/Profiles/Etc): No longer themable with our current method.
Position of notifications: Doesn't seem to be possible to change.
Height of sidebar items: Doesn't seem to be possible to increase.

Python 3
The skin is created and tested mostly on the Linux version of Steam. Steam's new UI has largely unified platform differences, so other platforms should work, but are not a priority.

<details><summary>Previews</summary>

</details>

git clone https://github.com/tkashkin/Adwaita-for-Steam
cd Adwaita-for-Steam
./install.py

Argument	Short	Required Values	Description
--color-theme	-c	Colortheme	Change color theme
--custom-css			Enable custom css
--extras	-e	Extra	Enable one or multiple theme extras
--list-options	-l		List available themes and extras
--target	-t	normal / flatpak / [custom dir]	Choose target location for install (default: both)
--uninstall	-u		Uninstall theme

# List options
./install.py -l
# Install with customizations
./install.py -c nord -e login/hide_qr -e library/hide_whats_new

<details><summary>Custom CSS</summary>

If you wish to include your own custom CSS, see custom and use the --custom-css flag.

./install.py --custom-css

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