nginx reverse poxy to a service on another wireguard peer

Before asking this question, I already self-searched but no solutions.

I have lots of services on my home server, and I bind it with a VPS by Wireguard (confirmed they can find each other). I hope to use nginx on VPS to reverse proxy to these services by proxy_pass http://10.0.0.2:xxxx

Now my case is, the service is can be find but only a pure empty page. The browser console show 404 error for all css and js file.

The related config is here:

server {
        listen       443 ssl http2;
        listen       [::]:443 ssl http2;
        server_name  _;
        root         /usr/share/nginx/html;

        ssl_certificate "/etc/pki/nginx/server.crt";
        ssl_certificate_key "/etc/pki/nginx/private/server.key";
        ssl_session_cache shared:SSL:1m;
        ssl_session_timeout  10m;
        ssl_ciphers PROFILE=SYSTEM;
        ssl_prefer_server_ciphers on;

        # Load configuration files for the default server block.
        include /etc/nginx/default.d/*.conf;

        error_page 404 /404.html;
        location = /404.html {
        }

        error_page 500 502 503 504 /50x.html;
        location = /50x.html {
        }

        location /cloud/ {
            proxy_pass http://10.0.0.2:5212/;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header Host $http_host;
            proxy_redirect off;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_set_header X-Scheme $scheme;

            client_max_body_size 20000m;
        }
    }

I would like to share more info or logs, just ask me. Thanks all your time.