anchor.diff:  
   (defparameter *default-encoding* :utf-8
     "Default document encoding.")
  +
  +(defparameter *default-viewport* "width=device-width, initial-scale=1"
  +  "Default document viewport.")
   
   (defun html-widget-meta (&key (content-type "text/html")
   			      (encoding *default-encoding*))
  
positive.code: 
     _encoding_—a _keyword_ denoting a character encoding. The default is
     {:utf-8}.
  
     *Description:*
  
  
negative.code:    _viewport_."
    (head
     (html-widget-meta :encoding encoding)
     (when viewport
       ;; The sad state of the web requires us to add this atrocious and
       ;; non-standard meta attribute because mobile browsers will render
       ;; HTML pages unresponsively otherwise.
       (meta :name "viewport" :content viewport))
     (when title
       (title title))
     (dolist (stylesheet stylesheets)
  