Use furo as theme for documentation

- the old theme didn't support dark mode

Author: mrbean-bremen

.readthedocs.yaml

@@ -11,3 +11,7 @@ build:
 sphinx:
   configuration: docs/source/conf.py
   fail_on_warning: true
+
+python:
+  install:
+    - requirements: docs/requirements.txt

CHANGELOG.md

@@ -9,6 +9,9 @@
 * use trusted publisher for release (see https://docs.pypi.org/trusted-publishers/)
 * use `pyproject.toml` for project setup
 
+### Documentation
+* use a theme for documentation supporting dark mode
+
 ### Documentation
 * added use case for ordering test modules (see [#51](https://github.com/pytest-dev/pytest-order/issues/51))
 

docs/requirements.txt

@@ -1 +1,2 @@
 sphinx>=2.3.1
+furo

docs/source/conf.py

@@ -104,7 +104,7 @@
 
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = "nature"
+html_theme = "furo"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the