server {
    listen 80;
    server_name _;

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

    location /api/ {
        # Matches the backend FILE_MAX_SIZE_MB (default 1m would reject uploads)
        client_max_body_size 25m;
        proxy_pass http://${BACKEND_UPSTREAM}/api/;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }

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