diff --git a/IPython/frontend/html/notebook/static/css/boilerplate.css b/IPython/frontend/html/notebook/static/css/boilerplate.css
index 062faf6..2b1535f 100644
--- a/IPython/frontend/html/notebook/static/css/boilerplate.css
+++ b/IPython/frontend/html/notebook/static/css/boilerplate.css
@@ -34,6 +34,9 @@ time, mark, audio, video {
vertical-align: baseline;
}
+sup { vertical-align: super; }
+sub { vertical-align: sub; }
+
article, aside, details, figcaption, figure,
footer, header, hgroup, menu, nav, section {
display: block;