code: function setFocus (hash) {
      var element = document.getElementById(hash.substring(1))
  
      if (element) {
        if (!/^(?:a|select|input|button|textarea)$/i.test(element.tagName)) {
          element.tabIndex = -1
        }
  
        element.focus()
      }
    }
docs: Adapted from: https://www.nczonline.net/blog/2013/01/15/fixing-skip-to-content-links/