Update Nginx Proxy Manager docs for the UI rewrite

docs/themes/nginx-proxy-manager.md

@@ -10,23 +10,49 @@ Custom [{{ page.title.split()[0] }}](https://github.com/NginxProxyManager/nginx-
 
 ### [Setup](/setup)
 
+The theme targets NPM's React UI, introduced in 2.13.0, and was verified with
+**Nginx Proxy Manager 2.15.1** in both native light and dark modes. Older UI
+versions are not supported by this rewrite.
+
 #### Docker
 
-Download the script from the theme.park repo `docker-mods/nginx-proxy-manager/root/etc/cont-init.d/98-themepark` and save it on your host.
+For the official `jc21/nginx-proxy-manager` image, download the
+[theme.park startup script](https://github.com/themepark-dev/theme.park/blob/master/docker-mods/nginx-proxy-manager/root/etc/cont-init.d/98-themepark)
+and make it executable:
 
-Mount the file to `/etc/cont-init.d/98-themepark` like so:
+```bash
+curl -fsSL https://raw.githubusercontent.com/themepark-dev/theme.park/master/docker-mods/nginx-proxy-manager/root/etc/cont-init.d/98-themepark -o 98-themepark-npm
+chmod +x 98-themepark-npm
+```
 
-```yml
+Add the script mount and theme settings to your existing NPM service:
+
+```yaml
+    environment:
+      TP_THEME: organizr
     volumes:
-      - /your/save/path/98-themepark-npm:/etc/cont-init.d/99-themepark
+      - /your/save/path/98-themepark-npm:/etc/cont-init.d/99-themepark:ro
 ```
 
-```bash
-    -v /your/save/path/98-themepark-npm:/etc/cont-init.d/99-themepark
-```
+Use the absolute path where you saved the script. Keep your existing NPM ports,
+data volumes and other settings. Recreate the container after adding the mount
+or changing a theme setting. Restarting the same container does not replace
+stylesheet links already inserted into its HTML.
+
+This image uses the mounted startup script, not the LinuxServer `DOCKER_MODS`
+environment variable.
 
-!!! Warning
-    Make sure the file is executable! `chmod +x 98-themepark-npm`
+| Variable | Default | Purpose |
+| --- | --- | --- |
+| `TP_THEME` | `organizr` | Theme option name, such as `aquamarine` or `nord`. |
+| `TP_COMMUNITY_THEME` | `false` | Set to `true` for a [community theme](/community-themes/), such as `catppuccin-latte`. |
+| `TP_DOMAIN` | `theme-park.dev` | CSS host, without a scheme. Set this when self-hosting theme.park. |
+| `TP_SCHEME` | `https` | Scheme used to fetch the CSS. |
+
+The script inserts two stylesheet links: the NPM base CSS and the selected theme
+option. Both must load. If the theme does not appear, check the container logs,
+the script's executable permission, and the browser's stylesheet requests.
+The CSS host must be reachable from your browser.
 
 {% set addons = extra.addons %}
 {% set title = page.title.split()[0].lower() %}
@@ -49,6 +75,8 @@ Mount the file to `/etc/cont-init.d/98-themepark` like so:
 
 ## Screenshots
 
+NPM 2.15.1 with sample hosts and the rewritten theme.
+
 {% set themes = config.extra.themes %}
 {% for theme in themes %}
 <p align="center">