Theming

Article last updated at August 11, 2026

Theming configures the visual appearance of the documentation.

You can manage the documentation theme using the configuration file theme.yaml in the project root, during build using the flag --theme, or in the root section of .yfm.

Defining the theme in the configuration file

File structure

The configuration file theme.yaml sets the color palette of your documentation. A color can be defined both globally for the light and dark themes, and separately for each.

Parameters specified in the light or dark sections take precedence over global values. If a variable is defined both in the main section and in the light or dark section, the value of the specific theme will be used.

A color can be specified in the format rgb, rgba, hex, hsl, hsla, or as a color name.

Example of a configuration file:

base-brand: rgb(152 223 37)
link: red

light:
    link: rgb(0 255 170)
    quote: rgb(255 0 255)

dark:
    quote: rgba(0, 208, 255, 1)
    base-background: hsl(30 46% 41%)

Parameter base-brand

The base-brand parameter is the main accent color of the theme. The following dependent parameters are automatically determined from the value of base-brand:

  • base-selection
  • link
  • link-hover
  • tab-active
  • tab-text
  • tab-text-hover
  • quote

Any variable value automatically calculated from the main accent color can be manually overridden in the configuration.

Parameters

All possible parameters are listed below.

Parameters Description
base-brand The main accent color. The color of tabs, quotes, and active switches.
base-background Page background.
base-selection The selected page in the table of contents and the selected dropdown item.
base-simple-hover Color when hovering over interface elements.
quote Quote color.
tab-active Active tab color.
tab-text Tab text color.
tab-text-hover Tab text color on hover.
link Link color.
link-hover Color of links, tab text, radio buttons, and accordion items on hover.
term-dfn-background Background of tooltips.
text-primary Main text, text in tables.
text-secondary Color of secondary text. Table of contents items, settings, language icons, etc.
line-generic Color of lines between page elements, external table borders, the common tab line, and the common article table of contents line.
code Text color in a code block.
code-background Background of a code block.
inline-code Text color in a code fragment.
inline-code-background Background of a code fragment.
table Text color in a table.
table-background Table background.
table-row-background Background color of highlighted table rows.
table-border Table border.
note-info-background Background color in the "Note" notice and in a notice with a custom title.
note-tip-background Background color in the "Tip" notice.
note-warning-background Background color in the "Important" note.
note-important-background Background color in the "Warning" note.
mini-toc-border Color of the article table of contents general line.
mini-toc Text color of the article table of contents.
mini-toc-hover Text color of the article table of contents on hover.
mini-toc-active Text color of the active item in the article table of contents.
mini-toc-active-border Line color of the active item in the article table of contents.

See also: Ajv schema of the themizer configuration theme.yaml

Defining base-brand during build

If there is no configuration file, the base-brand color can be set using the launch key --theme

For example:

yfm build -i ./input-folder -o ./output-folder --theme green

The base-brand color can also be set using a setting in the root section of .yfm.

For example:

theme: green

If both the setting in .yfm and the flag --theme are set simultaneously, the flag takes priority.

If both the configuration file and the flag --theme are set simultaneously, the flag will override the base-brand parameter only in the main section of the configuration file. Values in the light and dark sections remain unchanged.