diff --git a/public/gdb/index.md b/public/gdb/index.md
index 5ba6c75..67443a9 100644
--- a/public/gdb/index.md
+++ b/public/gdb/index.md
@@ -24,7 +24,7 @@ siblings:
 
 ### Table of Contents:
 
-{!{ <div style="columns: 2"> }!}
+{!{ <div class="two-column-list"> }!}
 
 1. [Introduction](#introduction)
 
diff --git a/scss/_markup.scss b/scss/_markup.scss
index 801daa1..4c8488b 100644
--- a/scss/_markup.scss
+++ b/scss/_markup.scss
@@ -150,3 +150,14 @@
     margin-bottom: 0;
   }
 }
+
+.two-column-list {
+  ol, ul {
+    @media (min-width: 500px) {
+      columns: 2;
+    }
+
+    li { margin-bottom: 0.5em; }
+    p { margin: 0; }
+  }
+}