Table of contents

  1. Color schemes
  2. Custom schemes
    1. Define a custom scheme
    2. Use a custom scheme
    3. Switchable custom scheme
  3. Override and define new variables
  4. Override and completely custom styles
  5. Override includes
    1. Custom TOC Heading
    2. Custom Footer
    3. Custom Head
    4. Custom Header
    5. Custom Nav Footer
    6. Custom Search Placeholder
  6. Custom layouts and includes
    1. Default layout and includable components
    2. Alternative layouts and example (minimal)
    3. Default layout and inheritance chain
    4. Overridden default Jekyll layouts

Color schemes

Just the Docs supports two color schemes: light (default), and dark.

To enable a color scheme, set the color_scheme parameter in your site’s _config.yml file:


# Color scheme supports "light" (default) and "dark"
color_scheme: dark

deprecated: legacy_light

New (v0.4.2)

In Just the Docs version 0.4.2, we changed the default syntax highlighting theme for the light color scheme to have higher contrast. Users who want to use the old highlighting need to explicitly opt-in with the deprecated legacy_light color scheme. In a future major release of Just the Docs, we will remove this color scheme.

Custom schemes

Define a custom scheme

You can add custom schemes. If you want to add a scheme named foo (can be any name) just add a file _sass/color_schemes/foo.scss (replace foo by your scheme name) where you override theme variables to change colors, fonts, spacing, etc.

Since the default color scheme is light, your custom scheme is implicitly based on the variable settings used by the light scheme.

If you want your custom scheme to be based on the dark scheme, you need to start your file with the following line:

@import "./color_schemes/dark";

You can define custom schemes based on other custom schemes in the same way.

Available variables are listed in the _variables.scss file.

For example, to change the link color from the purple default to blue, include the following inside your scheme file:


$link-color: $blue-000;

Keep in mind that changing a variable will not automatically change the value of other variables that depend on it. For example, the default link color ($link-color) is set to $purple-000. However, redefining $purple-000 in a custom color scheme will not automatically change $link-color to match it. Instead, each variable that relies on previously-cascaded values must be manually reimplemented by copying the dependent rules from _variables.scss — in this case, rewriting $link-color: $purple-000;.

Note: Editing the variables directly in _sass/support/variables.scss is not recommended and can cause other dependencies to fail. Please use scheme files.

Use a custom scheme

To use the custom color scheme, only set the color_scheme parameter in your site’s _config.yml file:

color_scheme: foo

Switchable custom scheme

If you want to be able to change the scheme dynamically, for example via javascript, just add a file assets/css/just-the-docs-foo.scss (replace foo by your scheme name) with the following content:

{% include css/just-the-docs.scss.liquid color_scheme="foo" %}

This allows you to switch the scheme via the following javascript.


Override and define new variables

New (v0.4.0)

To define new SCSS variables or functions, place SCSS code in _sass/custom/setup.scss. This should not be used for defining custom styles (see the next section) or overriding color scheme variables (in this case, you should create a new color scheme).

This is most commonly-used to define custom callout colors. For example,

// _sass/custom/setup.scss
$pink-000: #f77ef1;
$pink-100: #f967f1;
$pink-200: #e94ee1;
$pink-300: #dd2cd4;

In particular: this file is imported after the theme’s variables and functions are defined, but before any CSS classes are emitted.

Override and completely custom styles

For styles that aren’t defined as SCSS variables, you may want to modify specific CSS classes. Additionally, you may want to add completely custom CSS specific to your content. To do this, put your styles in the file _sass/custom/custom.scss. This will allow for all overrides to be kept in a single file, and for any upstream changes to still be applied.

For example, if you’d like to add your own styles for printing a page, you could add the following styles.


// Print-only styles.
@media print {
  .page-header {
    display: none;
  .main-content {
    max-width: auto;
    margin: 1em;

Override includes

You can customize the theme by overriding any of the custom Jekyll includes files that it provides.

To do this, create an _includes directory and make a copy of the specific file you wish to modify. The content in this file will override the theme defaults. You can learn more about this process in the Jekyll docs for Overriding theme defaults.

Just the Docs provides the following custom includes files:

Custom TOC Heading

New (v0.4.0)


If the page has any child pages, and has_toc is not set to false, this content appears as a heading above the auto-generating list of child pages after the page’s content.


To change the default TOC heading to “Contents”, create _includes/toc_heading_custom.html and add:

<h2 class="text-delta">Contents</h2>

The (optional) text-delta class makes the heading appear as Contents .


This content appears at the bottom of every page’s main content. More info for this include can be found in the Configuration - Footer content.

Custom Head


Any HTML added to this file will be inserted before the closing <head> tag. This might include additional <meta>, <link>, or <script> tags.

The <head> tag automatically includes a link to an existing favicon if you set favicon_ico to the corresponding path in your configuration, or if the path to the favicon is /favicon.ico.

Custom Header


Content added to this file appears at the top of every page’s main content between the site search and auxiliary links if they are enabled. If search_enabled were set to false and aux_links were removed, the content of header_custom.html would occupy the space at the top of every page.

New (v0.4.0)


Any content added to this file will appear at the bottom left of the page below the site’s navigation. By default an attribution to Just the Docs is displayed which reads, This site uses Just the Docs, a documentation theme for Jekyll..

Custom Search Placeholder

New (v0.4.0)


Content added to this file will replace the default placeholder text in the search bar (and its aria-label), after stripping HTML and leading/trailing whitespace. By default, the content of the include is:

Search {{site.title}}

Override this file to render a custom placeholder. One common use-case is internationalization; for example,

Chercher notre site

would make the placeholder text “Chercher notre site”. Liquid code (including Jekyll variables) is also supported.

Custom layouts and includes

New (v0.4.0)


Just the Docs uses Jekyll’s powerful layouts and includes features to generate and compose various elements of the site. Jekyll users and developers can extend or replace existing layouts and includes to customize the entire site layout.

Default layout and includable components

The default layout is inherited by most of the “out-of-the-box” pages provided by Just the Docs. It composes various re-usable components of the site, including the sidebar, navbar, footer, breadcrumbs, and various imports. Most users who create new pages or layouts will inherit from default.

Here is a simplified code example of what it looks like:

<!-- a simplified version of _layouts/default.html -->
{% include head.html %}
  {% include icons/icons.html %}
  {% include components/sidebar.html %}
  {% include components/header.html %}
  {% include components/breadcrumbs.html %}

  {% if site.heading_anchors != false %}
    {% include vendor/anchor_headings.html html=content ... %}
  {% else %}
    {{ content }}
  {% endif %}

  {% if page.has_children == true and page.has_toc != false %}
    {% include components/children_nav.html %}
  {% endif %}

  {% include components/footer.html %}

  {% if site.search_enabled != false %}
    {% include components/search_footer.html %}
  {% endif %}

  {% if site.mermaid %}
    {% include components/mermaid.html %}
  {% endif %}

Component summary

Defining a new _includes with the same name as any of these components will significantly change the existing layout. Please proceed with caution when adjusting them.

To briefly summarize each component:

  • _includes/head.html is the entire <head> tag for the site; this imports stylesheets, various JavaScript files (ex: analytics, mermaid, search, and Just the Docs code), and SEO / meta information.
  • _includes/icons/icons.html imports all SVG icons that are used throughout the site. Some, such as those relating to search or code snippet copying, are only loaded when those features are enabled.
  • _includes/components/sidebar.html renders the sidebar, containing the site header, navigation links, external links, collections, and nav footer.
  • _includes/components/header.html renders the navigation header, containing the search bar, custom header, and aux links
  • _includes/components/breadcrumbs.html renders the breadcrumbs feature
  • vendor/anchor_headings.html is a local copy of Vladimir Jimenez’s jekyll-anchor-headings snippet
  • _includes/components/children_nav.html renders a list of nav links to child pages on parent pages
  • _includes/components/footer.html renders the bottom-of-page footer
  • _includes/components/search_footer.html renders DOM elements that are necessary for the search bar to work
  • _includes/components/mermaid.html initializes mermaid if the feature is enabled

Each of these components can be overridden individually using the same process described in the Override includes section. In particular, the granularity of components should allow users to replace certain components (such as the sidebar) without having to adjust the rest of the code.

Future versions may subdivide components further; we guarantee that we will only place them in folders (ex components/, icons/, or a new js/) to avoid top-level namespace collisions.

Alternative layouts and example (minimal)

Users can develop custom layouts that compose, omit, or add components differently. We provide one first-class example titled minimal, which disables the navigation sidebar. To see an example, visit the minimal layout test page.

Users can indicate this alternative layout in page front matter:

layout: minimal
title: Minimal layout test

Similarly, users and developers can create other alternative layouts using Just the Docs’ reusable includable components.

Default layout and inheritance chain

Under the hood,

  • default inherit from the table_wrappers layout, which wraps all HTML <table> tags with a div .table-wrapper
  • table_wrappers inherits from vendor/compress, which is a local copy of Anatol Broder’s jekyll-compress-html Jekyll plugin

The minimal layout inherits from the default but assigns nav_enabled: false to disable the navigation sidebar.

Overridden default Jekyll layouts

By default, Jekyll (and its default theme minima) provide the about, home, page, and post layouts. In Just the Docs, we override all of these layouts with the default layout. Each of those layouts is simply:

layout: default

{{ content }}