server {
    listen 80;
    listen [::]:80;
    server_name _;

    root /usr/share/nginx/html;

    # Logging
    access_log /var/log/nginx/frontend-access.log main;
    error_log /var/log/nginx/frontend-error.log warn;

    # 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;

    # Gzip compression
    gzip on;
    gzip_types text/plain text/css text/xml text/javascript 
               application/x-javascript application/xml+rss 
               application/json application/javascript;
    gzip_min_length 1000;

    # Serve static files with SPA fallback
    location / {
        try_files $uri $uri/ /index.html;
    }

    # Cache static assets (60 days)
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|webp|woff|woff2|ttf|eot)$ {
        expires 60d;
        add_header Cache-Control "public, immutable";
    }

    # Don't cache HTML files
    location ~* \.html$ {
        expires -1;
        add_header Cache-Control "no-cache, no-store, must-revalidate";
    }

    # Health check
    location /health {
        access_log off;
        return 200 "OK\n";
        add_header Content-Type text/plain;
    }

    # Deny access to sensitive files
    location ~ /\. {
        deny all;
        access_log off;
        log_not_found off;
    }
}