nginx.conf

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

    # 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 Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self'; connect-src 'self' https://*.stellar.org https://api.coingecko.com; img-src 'self' data: https:; font-src 'self'; object-src 'none'; base-uri 'self'; upgrade-insecure-requests;" always;

    # Health check endpoint
    location /health {
        return 200 'ok';
        add_header Content-Type text/plain;
    }

    # Cache static assets
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff2?)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
    }

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