diff --git a/pyproject.toml b/pyproject.toml
index 457f769..c093d51 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,7 +23,7 @@ requires-python = ">=3.8"
 
 [project.optional-dependencies]
 doc = [
-    "sphinx>5.0",
+    "sphinx>5.0,<8.2",
     "sphinx_rtd_theme",
     "sphinx_copybutton",
     "sphinx_design",