Error: Invalid CSS selector in bizstyle.js

Describe the bug

Google Chrome 108.0.5359.124:

Uncaught DOMException: Failed to execute 'querySelectorAll' on 'Document': 'div.related:first ul li:not(.right) a' is not a valid selector.
    at HTMLDocument.initialiseBizStyle (file:///Users/phprus/....../build/html/_static/bizstyle.js:21:14)
initialiseBizStyle @ bizstyle.js:21

and

Uncaught DOMException: Failed to execute 'querySelectorAll' on 'Document': 'div.related:last ul li:not(.right) a' is not a valid selector.

FireFox 108.0.1:

Uncaught DOMException: Document.querySelectorAll: 'div.related:first ul li:not(.right) a' is not a valid selector bizstyle.js:21
    initialiseBizStyle file:///Users/phprus/....../build/html/_static/bizstyle.js:21

How to Reproduce

$ echo "Content demonstrating the bug..." > index.rst
$ echo "html_theme = 'bizstyle'" > conf.py
$ sphinx-build -M html . _build
$ # open _build/html/index.html and see exception on browser console

Environment Information

Platform:              darwin; (macOS-12.6.2-arm64-arm-64bit)
Python version:        3.11.0 (main, Oct 25 2022, 13:57:33) [Clang 14.0.0 (clang-1400.0.29.202)])
Python implementation: CPython
Sphinx version:        5.3.0
Docutils version:      0.19
Jinja2 version:        3.1.2

Sphinx extensions

No response

Additional context

No response

Reproduce the issue with index.rst and conf.py using sphinx-build, then inspect build/html/_static/bizstyle.js at line 21 and the source for the bizstyle theme. Confirm the generated page loads without querySelectorAll selector errors in Chrome and Firefox.