diff --git a/pelicanconf.py b/pelicanconf.py
index 8913fdc..22efd31 100644
--- a/pelicanconf.py
+++ b/pelicanconf.py
@@ -68,7 +68,8 @@ PLUGIN_PATHS = ['pelican-plugins']
 PLUGINS = ['liquid_tags.youtube', 'liquid_tags.vimeo', 'liquid_tags.notebook']
 
 NOTEBOOK_DIR = 'notebooks'
-EXTRA_HEADER = open('_nb_header.html').read().decode('utf-8')
+EXTRA_HEADER = open('_nb_header.html').read().decode('utf-8').replace(
+    'highlight', 'highlight-ipynb')
 
 LOAD_CONTENT_CACHE = True