diff --git a/requirements.txt b/requirements.txt
index f6215c5..eeb0f40 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 Sphinx
-Pygments==2.2.0
+Pygments==2.7.4
 sphinx-autobuild
 sphinx_rtd_theme==0.2.5b1
 sphinxcontrib-images