diff --git a/assets/app.scss b/assets/app.scss
index 570e6d88215f336757b082d4747987346034349a..7fc35cdde4299fe69c0f4f1d59b25d6ea11830b4 100644
--- a/assets/app.scss
+++ b/assets/app.scss
@@ -1,3 +1,14 @@
+// visible code blocks
+
+pre {
+  padding: .75rem;
+  color: #fff;
+  background: #212529;
+  border-radius: .25rem;
+}
+
+// dark theme switcher
+
 .theme-switch {
   display: inline-block;
   height: 24px;