anchor.diff:    verso_content:
       left: '{page-number} | {chapter-title}'
   ----
  +
  +==== Images
  +
  +You can add an image to the running header or footer using the AsciiDoc inline image syntax.
  +Note that the image must be the whole value for a given position (left, center or right).
  +It cannot be combined with text.
  +
  +Here's an example of how to use an image in the running footer.
  +
  +[source,yaml]
  +----
  +footer:
  +  height: 0.75in
  +  image_valign: 2 # <1>
  +  recto_content:
  +    left: image:footer-logo.png[width=80]
  +    right: '{page-number}'
  +  verso_content:
  +    left: $footer_recto_content_right
  +    right: $footer_recto_content_left
  +----
  +<1> You can use the `footer_valign` attribute to slighly nudge the image up or down.
  +
  +CAUTION: The image must fit in the allotted space for the running header or footer.
  +Otherwise, you will run into layout issues.
  +Adjust the width attribute accordingly.
   
   == Applying your theme
   
  
positive.code: * section-title
  * section-or-chapter-title
  
  For example:
  
  [source,yaml]
  ----
  
negative.code: NOTE: The background color spans the width of the page.
  When a background color is specified, the border also spans the width of the page.
  
  ==== Implicit attributes
  
  In addition to the document-level attributes defined in the AsciiDoc document, the following attributes are available when defining the content keys in the footer:
  
  * page-count
  