:4321 {
    root * /srv
    file_server

    # Handle clean URLs - try file, then directory, then .html extension
    try_files {path} {path}/ {path}.html /index.html

    # Compression
    encode gzip

    # Service worker must not be cached
    @sw path /sw.js
    header @sw Cache-Control "no-cache, no-store, must-revalidate"

    # Cache static assets
    @static {
        path *.jpg *.jpeg *.png *.gif *.ico *.css *.js *.pdf *.svg *.woff *.woff2
    }
    header @static Cache-Control "public, max-age=604800, immutable"

    # Security headers
    header X-Frame-Options "SAMEORIGIN"
    header X-Content-Type-Options "nosniff"
}