gnome-shell/data/theme
Florian Müllner a87ab6d0fc panel: Restrict app menu width
Window titles aren't restricted in length, so the menu may end up unwieldily
width. Commit 0bec76b6ee therefore limited the app context menus, but that
got accidentally dropped in commit 0ded0dbfd5. Add back the limitation and
extend it to the new app menu as well.

https://gitlab.gnome.org/GNOME/gnome-shell/issues/624
2019-02-06 18:29:15 +01:00
..
gnome-shell-sass
calendar-today.svg
checkbox-focused.svg
checkbox-off-focused.svg
checkbox-off.svg
checkbox.svg
dash-placeholder.svg
gnome-shell-high-contrast.scss
gnome-shell.scss
key-enter.svg
key-hide.svg
key-layout.svg
key-shift-latched-uppercase.svg
key-shift-uppercase.svg
key-shift.svg
meson.build
message-indicator-symbolic.svg
no-events.svg
no-notifications.svg
noise-texture.png
pad-osd.css
process-working.svg
README.md
running-indicator.svg
toggle-off-hc.svg
toggle-off-intl.svg
toggle-off-us.svg
toggle-on-hc.svg
toggle-on-intl.svg
toggle-on-us.svg

Summary

Do not edit the CSS directly, edit the source SCSS files and the CSS files will be generated automatically when building with meson + ninja and left inside the build directory to be incorporated into the gresource XML (you'll need to have sassc installed).

How to tweak the theme

Adwaita is a complex theme, so to keep it maintainable it's written and processed in SASS, the generated CSS is then transformed into a gresource file during gtk build and used at runtime in a non-legible or editable form.

It is very likely your change will happen in the _common.scss file. That's where all the widget selectors are defined. Here's a rundown of the "supporting" stylesheets, that are unlikely to be the right place for a drive by stylesheet fix:

File Description
_colors.scss global color definitions. We keep the number of defined colors to a necessary minimum, most colors are derived from a handful of basics. It is an exact copy of the gtk+ counterpart. Light theme is used for the classic theme and dark is for GNOME3 shell default.
_drawing.scss drawing helper mixings/functions to allow easier definition of widget drawing under specific context. This is why Adwaita isn't 15000 LOC.
_common.scss actual definitions of style for each widget. This is where you are likely to add/remove your changes.

You can read about SASS on its web page. Once you make your changes to the _common.scss file, you can run ninja to generate the final CSS files.