diff --git a/requirements.txt b/requirements.txt
index 541791b..9719324 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-Sphinx
+sphinx < 8.0
 sphinx_rtd_theme
 myst_nb
 git+https://github.com/rkdarst/sphinx-copybutton.git@exclude-unselectable-3