Changing colors

Furo allows customising colors to fit your brand’s identity, by using CSS variables. These can be declared directly in html_theme_options, in your conf.py.

How light and dark mode work

Furo is in light mode by default, switching to the dark mode when requested by the user’s browser (through prefers-color-scheme: dark).

As a consequence of this design, the dark mode inherits the variable definitions from the light mode, only overriding specific values to adapt the theme. While the mechanism for switching between light/dark mode is not configurable, the exact CSS variable definitions used in this process can be configured.

Defining overrides for defaults

Furo allows defining CSS variables that overrides its default values. The exact variable names to use can be found in Furo’s source code, where the variable declarations are made.

This mechanism allows configuring nearly every facet of Furo’s design, including spacing between various items and the colors of nearly every component.

Example

Changing Furo’s blue accent (used for stylising links, sidebar’s content etc) to a purple one:

html_theme_options = {
    "light_css_variables": {
        "color-brand-primary": "#7C4DFF",
        "color-brand-content": "#7C4DFF",
    },
    "dark_css_variables": {
        "color-brand-primary": "#7C4DFF",
        "color-brand-content": "#7C4DFF",
    },
}

Code block styling

Furo does not directly handle highlighting of the code blocks. This is done by Sphinx, and is configurable using pygments_style and pygments_dark_style in conf.py.

pygments_style = "sphinx"
pygments_dark_style = "monokai"

Note

pygments_dark_style is Furo-specific at this time.