anchor.diff:  |link:
     font_color: #428bca
   
  -|font_family
  -|<<fonts,Font family name>>
  -|link:
  -  font_family: Roboto
  -
  -|font_size
  -|<<values,Number>>
  -|link:
  -  font_size: 9
  -
  -|font_style
  -|normal {vbar} italic {vbar} bold {vbar} bold_italic
  -|link:
  -  font_style: normal
  +// font_family, font_size and font_style not yet implemented
  +//|font_family
  +//|<<fonts,Font family name>>
  +//|link:
  +//  font_family: Roboto
  +//
  +//|font_size
  +//|<<values,Number>>
  +//|link:
  +//  font_size: 9
  +//
  +//|font_style
  +//|normal {vbar} italic {vbar} bold {vbar} bold_italic
  +//|link:
  +//  font_style: normal
   |===
   
   === Literal inline
  
positive.code: |heading:
    margin_bottom: 9.6
  
  3+|*Key Prefix:* heading_h<n>^[1]^
  
  |align
  |left {vbar} center {vbar} right {vbar} justify
  |heading:
    h2_align: center
  
  |font_color
  |<<colors,Color>>
  |heading:
    h2_font_color: [0, 99%, 100%, 0]
  
  |font_family
  |<<fonts,Font family name>>
  |heading:
    h4_font_family: Roboto
  
  |font_size
  |<<values,Number>>
  |heading:
    h6_font_size: $base_font_size * 1.7
  
  |font_style
  |normal {vbar} italic {vbar} bold {vbar} bold_italic
  |heading:
    h3_font_style: bold_italic
  |===
  
  . `<n>` is a number ranging from 1 to 6, representing each of the six heading levels.
  
negative.code: 3+|*Key Prefix:* heading
  
  |align
  |left {vbar} center {vbar} right {vbar} justify +
  (default: left)
  |heading:
    align: center
  
  |font_color
  |<<colors,Color>> +
  (default: $base_font_color)
  |heading:
    font_color: #222222
  
  |font_family
  |<<fonts,Font family name>> +
  (default: $base_font_family)
  |heading:
    font_family: Noto Serif
  
  |font_size
  |<<values,Number>> +
  (default: $base_font_size)
  |heading:
    font_size: 18
  
  |font_style
  |normal {vbar} italic {vbar} bold {vbar} bold_italic +
  