nginx.conf

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

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript application/javascript application/xml+rss application/json;

    # Security headers
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-XSS-Protection "0" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
    # Security: CSP allows jsdelivr CDN (Pyodide), unpkg (sandbox), esm.sh (ERC-8004), and inline scripts/eval
    # All fonts are self-hosted. Monaco Editor is bundled locally. Explicit script-src-elem/style-src-elem prevent fallback issues.
    add_header Content-Security-Policy "default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval' https://cdn.jsdelivr.net https://unpkg.com https://cdn.tailwindcss.com https://esm.sh https://binaries.soliditylang.org; script-src-elem 'self' 'unsafe-inline' https://cdn.jsdelivr.net https://unpkg.com https://cdn.tailwindcss.com https://esm.sh https://binaries.soliditylang.org; style-src 'self' 'unsafe-inline' https://cdn.jsdelivr.net; style-src-elem 'self' 'unsafe-inline' https://cdn.jsdelivr.net; img-src 'self' data: https:; font-src 'self' data:; connect-src 'self' https: wss:; worker-src 'self' blob:; frame-src 'self' blob:; frame-ancestors 'self'; manifest-src 'self'" always;
    add_header Permissions-Policy "camera=(), microphone=(), geolocation=()" always;

    # SPA routing - serve index.html for all routes
    location / {
        try_files $uri $uri/ /index.html;
    }

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

    # Cache HTML files for shorter time
    location ~* \.(html)$ {
        expires 1h;
        add_header Cache-Control "public";
    }

    # Disable logging for favicon and robots
    location = /favicon.ico {
        log_not_found off;
        access_log off;
    }

    location = /robots.txt {
        log_not_found off;
        access_log off;
    }

    # Error pages
    error_page 404 /index.html;
}