init: seth-linux-theme scaffold with GTK CSS, kitty, and GNOME configs

install.sh

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# Install Seth Linux Theme to target user's ~/.config
+set -euo pipefail
+
+TARGET_HOME="${1:-$HOME}"
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+
+echo "Installing seth-linux-theme to $TARGET_HOME/.config ..."
+
+# GTK CSS (same file for both GTK3 and GTK4)
+mkdir -p "$TARGET_HOME/.config/gtk-3.0" "$TARGET_HOME/.config/gtk-4.0"
+cp "$SCRIPT_DIR/gtk-3.0/gtk.css" "$TARGET_HOME/.config/gtk-3.0/gtk.css"
+cp "$SCRIPT_DIR/gtk-3.0/gtk.css" "$TARGET_HOME/.config/gtk-4.0/gtk.css"
+echo "  GTK CSS installed."
+
+# Kitty theme conf
+if [ -d "$TARGET_HOME/.config/kitty" ]; then
+    cp "$SCRIPT_DIR/kitty/kitty-theme.conf" "$TARGET_HOME/.config/kitty/kitty-theme.conf"
+    if ! grep -q "include kitty-theme.conf" "$TARGET_HOME/.config/kitty/kitty.conf" 2>/dev/null; then
+        echo "" >> "$TARGET_HOME/.config/kitty/kitty.conf"
+        echo "include kitty-theme.conf" >> "$TARGET_HOME/.config/kitty/kitty.conf"
+    fi
+    echo "  Kitty theme installed."
+else
+    echo "  Kitty config dir not found, skipping."
+fi
+
+# GNOME settings (only if running a GNOME session)
+if command -v gsettings &>/dev/null; then
+    bash "$SCRIPT_DIR/gnome/apply-gnome-settings.sh"
+else
+    echo "  gsettings not found, skipping GNOME settings."
+fi
+
+echo "Done. Open new windows to see changes. Relaunch kitty for kitty changes."