/*
  X-Content-Type-Options: nosniff
  Referrer-Policy: strict-origin-when-cross-origin
  Permissions-Policy: camera=(), microphone=(), geolocation=()
  Cache-Control: public, max-age=0, must-revalidate

/thumbs/*
  Cache-Control: public, max-age=86400

/downloads/*
  Cache-Control: public, max-age=3600

/downloads/*.zip
  Content-Disposition: attachment; filename="lanshu-html-ppt-templates.zip"
