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

    # Gzip static text assets
    gzip on;
    gzip_vary on;
    gzip_types text/plain text/css application/javascript application/json image/svg+xml;

    # Long cache for fingerprint-free static assets; short cache for HTML so
    # deploys show up without needing a hard-refresh.
    location ~* \.(?:css|js|png|jpg|jpeg|svg|ico|woff2?)$ {
        expires 7d;
        add_header Cache-Control "public, max-age=604800, immutable";
    }

    location / {
        try_files $uri $uri/ /index.html;
        add_header Cache-Control "no-cache";
    }

    # Basic hardening headers
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;

    error_page 404 /index.html;
}