server {
  listen 80;
  server_name _;

  root /usr/share/nginx/html;
  index index.html;

  location / {
    try_files $uri $uri/ /index.html;
  }

  location /config.js {
    add_header 'Access-Control-Allow-Origin' '*';
    add_header 'Content-Type' 'application/javascript';
  }
}