diff --git a/styles/custom.css b/styles/custom.css
index aee84fdd3fa6e4bb4c216b80f1ed5bdb98919942..2bfc5ba144979594e9c70763a667633d278f2254 100644
--- a/styles/custom.css
+++ b/styles/custom.css
@@ -1,5 +1,5 @@
 /* Remove the vertical scrollbar added by nbconvert. */
-.reveal {
+html {
   overflow-y: hidden;
 }