diff --git a/style/shiny/base.css b/style/shiny/base.css
index 4547617..50e342d 100644
--- a/style/shiny/base.css
+++ b/style/shiny/base.css
@@ -196,6 +196,16 @@ dd + dt {
 }
 
 
+.threecol {
+  columns: 3;
+  column-gap: 2em;
+}
+
+.threecol dd {
+  break-before: avoid;
+}
+
+
 @media (prefers-color-scheme: dark) {
   :root {
     --gradient: