anchor.diff:      align: right
   
   |image
  -|image macro^[2]^ +
  +|image macro^[3]^ +
   (default: _not set_)
   |title-page:
     logo:
       image: image:logo.png[pdfwidth=25%]
   
   |top
  -|Percentage^[3]^ +
  +|Percentage^[4]^ +
   (default: 10%)
   |title-page:
     logo:
  
positive.code: |title-page:
    background-color: #eaeaea
  
  |background-image^[1]^
  |image macro^[2]^ +
  (default: _not set_)
  |title-page:
    background-image: image:title.png[]
  
negative.code: . The path is resolved relative to base_dir.
  . The target of the image macro is resolved relative to `imagesdir`.
  If the image macro syntax is not used, the value is resolved relative to the base directory, which defaults to the document directory.
  . By default, page background images are automatically scaled to fit the bounds of the page (i.e., `fit=contain`) and centered (i.e., `position=center`).
  The size of the background image can be controlled using any of the sizing attributes on the image macro (i.e., fit, pdfwidth, scaledwidth, or width).
  The position of the background image can be controlled using the `position` attribute.
  If the recto (right-hand, odd-numbered pages) or verso (left-hand, even-numbered pages) background is specified, it will be used only for that side.
  If a background image isn't specified for a side, the converter will use the default page background image (`page-background-image`), if specified.
  To disable the background image for a side, use the value `none`.
  . Controls whether the `page-number` attribute is accessible to the running header and footer content specified in the theme file.
  Use the `noheader` and `nofooter` attributes to disable the running header and footer, respectively, from the document.
  . Enables generation of the http://milan.kupcevic.net/ghostscript-ps-pdf/#marks[pdfmark] file, which contains metadata that is fed to Ghostscript when optimizing the PDF file.
  