Qt apps (e.g. VLC) rendered in the default Fusion style — GTK theming
does not cover Qt. Add the Kvantum style engine + Catppuccin Mocha
Lavender theme, wired via QT_STYLE_OVERRIDE, which covers both Qt5 and
Qt6 (QT_QPA_PLATFORMTHEME can select only one plugin at a time).
Also move all GUI-toolkit env vars (QT_*/GDK/SDL/CLUTTER) from zshrc to
niri's environment{} block: niri is systemd-started, so zsh exports
never reached niri-spawned GUI apps (verified via /proc/environ), only
terminal-launched ones — the app launcher included.
- packages: kvantum, kvantum-qt5, qt6ct + kvantum-theme-catppuccin-git (AUR)
- niri config.kdl: environment{} block; zshrc: GUI-toolkit vars removed
- qt6ct.conf (style=kvantum, icon_theme=Colloid), Kvantum/kvantum.kvconfig
(theme=catppuccin-mocha-lavender, the Lavender accent)
- CLAUDE.md + DECISIONS.md