Rename index.html to background.html; configure nginx to serve it as index

Dockerfile

@@ -5,7 +5,7 @@ COPY gruvbox.css /usr/share/nginx/html/gruvbox.css
 COPY nord.css /usr/share/nginx/html/nord.css
 COPY config.js /usr/share/nginx/html/config.js
 COPY i18n.js /usr/share/nginx/html/i18n.js
-COPY index.html /usr/share/nginx/html/index.html
+COPY background.html /usr/share/nginx/html/background.html
 COPY noise.png /usr/share/nginx/html/noise.png
 COPY vendor/ /usr/share/nginx/html/vendor/
 EXPOSE 58881

default.conf

@@ -2,7 +2,7 @@ server {
     listen 58881 default_server;
     server_name localhost;
     root /usr/share/nginx/html;
-    index index.html;
+    index background.html;
 
     location / {
         try_files $uri $uri/ =404;