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

    # Gzip compression
    gzip on;
    gzip_types text/plain text/css application/json application/javascript text/xml application/xml text/javascript image/svg+xml;
    gzip_min_length 1000;

    # Security headers
    add_header X-Frame-Options "SAMEORIGIN";
    add_header X-Content-Type-Options "nosniff";
    add_header X-XSS-Protection "1; mode=block";

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

    location /api/ {
        proxy_pass http://backend:8080;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
        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;
    }

    # Cache static assets
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg)$ {
        expires 30d;
        add_header Cache-Control "public, no-transform";
    }
}