diff --git a/web/markdown/markdown-spoiler.react.js b/web/markdown/markdown-spoiler.react.js
--- a/web/markdown/markdown-spoiler.react.js
+++ b/web/markdown/markdown-spoiler.react.js
@@ -4,6 +4,8 @@
 
 import type { ReactElement } from 'lib/shared/markdown';
 
+import css from './markdown.css';
+
 type MarkdownSpoilerProps = {
   +text: ReactElement,
 };
@@ -12,7 +14,7 @@
   function MarkdownSpoiler(props: MarkdownSpoilerProps): React.Node {
     const { text } = props;
 
-    return <span>{text}</span>;
+    return <span className={css.spoiler}>{text}</span>;
   },
 );
 
diff --git a/web/markdown/markdown.css b/web/markdown/markdown.css
--- a/web/markdown/markdown.css
+++ b/web/markdown/markdown.css
@@ -39,6 +39,11 @@
   background: #222222;
   color: #f3f3f3;
 }
+span.spoiler {
+  background: #33332c;
+  color: #33332c;
+  cursor: pointer;
+}
 
 div.markdown pre {
   padding: 0.5em 10px;