diff --git a/requirements.docs.txt b/requirements.docs.txt
index 67493140..1a71f097 100644
--- a/requirements.docs.txt
+++ b/requirements.docs.txt
@@ -1,5 +1,5 @@
 sphinx>=4
-sphinx_rtd_theme
+sphinx_rtd_theme>1
 sphinxcontrib-apidoc
 sphinx-github-style
 pyyaml