How to add custom CSS file to Sphinx?

Question

How can I add a custom CSS file? The following conf.py does not work:

html_static_path = ['_static']
html_theme = 'default'
html_theme_options = {
  'cssfiles': ['_static/style.css']
}

Result:

$ make html
Running Sphinx v1.2.2
loading pickled environment... not yet created
building [html]: targets for 2 source files that are out of date
updating environment: 2 added, 0 changed, 0 removed
reading sources... [ 50%] help
reading sources... [100%] index

looking for now-outdated files... none found
pickling environment... done
checking consistency... done
preparing documents...
Theme error:
unsupported theme option 'cssfiles' given

Banish

Related question: #32079700 – Babbage

Answer 1

A simpler way is to add this to your conf.py:

def setup(app):
    app.add_css_file('css/custom.css')  # may also be an URL

Then put the file into the _static/css/ folder.

Feliks

add javascript files via app.add_javascript('file.js'). – Godsey

After doing that, I still have to manually add a reference to the css in the html file... Anything more automatic? – Chessman

@Chessman been a while, but may be a function of the theme. – Feliks

perhaps worthwhile to note that alabaster theme works out-of-the box with a _static/custom.css file in source folder so add_styleshee('custom.css') would not be needed for this theme. – Aho

This works with this line: html_static_path = ['_static'] – Duax

Answer 2

You should be able to include custom css by extending the default sphinx theme. In your conf.py you would specify where your extension to the theme would be, such as.

# Add any paths that contain templates here, relative to this directory.
templates_path = ['_templates']

Then in _templates you would create a extension to the default theme named 'layout.html' that would include your cssfiles such as.

{# layout.html #}
{# Import the layout of the theme. #}
{% extends "!layout.html" %}

{% set css_files = css_files + ['_static/style.css'] %}

See sphinx's documentation on templating for more information.

Viradis

Could you explain, what is symbol ! means? – Banish

"By prefixing the name of the overridden template with an exclamation mark, Sphinx will load the layout template from the underlying HTML theme." I've added a link to the sphinx documentation on templating above. Mainly that line is called to extend the default sphinx layout.html, or whatever theme you might have installed. – Viradis

Thx, one more question plz: You example work as expected after make html, but does not work on readthedocs.org with default theme(sphinx_rtd_theme). – Banish

You are correct. I just pulled the sphinx_rtd_theme down and tried to extend the theme with my custom css, and the sphinx_rtd_theme overrides that css. I searched the github issues and this seems to be a problem with other css as well. github issue 117. I'll continue to play with it and see, if I can get it to work with the theme, but it seems to be a current limitation of sphinx_rtd_theme as mentioned in that issue. – Viradis

Thx for the link, add_stylesheet solved my problem. – Banish

I noticed that the css will not be rebuilt when I use sphinx-autobuild. – Camp

FTR the templating link is now sphinx-doc.org/en/master/templating.html. SO wouldn't let me suggest an edit to the answer for some reason so I'm pointing it here. – Quintinquintina

Answer 3

The options that you can configure via html_theme_options are theme-dependent. Check out the [options] section of your theme’s theme.conf to find out what is available.

On a global basis, though, you can define html_context in your conf.py to override the settings for css_files (and, for that matter, script_files too):

html_context = {
    'css_files': ['_static/custom.css'],
}

(For reference, have a look at Sphinx’s builders.html.StandaloneHTMLBuilder.prepare_writing() and see how self.globalcontext gets populated there.)

Skirling

Thank you! Out of the answers provided, this is what helped me override annoying auto-hyphenation in the basic.css. – Karmen

The link is now dead. – Osteophyte

Answer 4

I'm using Sphinx 3.2.

I was able to add some simple custom CSS by doing the following:

• add this line in conf.py right under html_static_path = ['_static']:

html_css_files = ['css/custom.css']

• go to docs/_static/ and add css/custom.css

• add custom css to your file then $ make html

Source

Gemmiparous

This is the approach recommended by ReadTheDocs and Furo – Babbage