server {
    listen 80;
    root /usr/share/nginx/html;
    index index.html;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_min_length 1024;
    gzip_types
        text/plain
        text/css
        text/javascript
        application/javascript
        application/json
        application/xml
        image/svg+xml;

    # Security headers
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
    add_header Permissions-Policy "camera=(), microphone=(), geolocation=()" always;

    # Static assets — long-lived cache with immutable flag
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
    }

    # API proxy → backend (preserve full /api/ prefix)
    location /api/ {
        proxy_pass http://backend:8000/api/;
        proxy_http_version 1.1;
        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;
        proxy_read_timeout 60s;
        proxy_connect_timeout 10s;
    }

    # SPA fallback — all unknown routes serve index.html
    location / {
        try_files $uri $uri/ /index.html;
    }
}