diff --git a/curriculum/challenges/english/01-responsive-web-design/learn-css-colors-by-building-a-color-markers-set/step-004.md b/curriculum/challenges/english/01-responsive-web-design/learn-css-colors-by-building-a-color-markers-set/step-004.md
index a25c4b9f6c..aa336b0f71 100644
--- a/curriculum/challenges/english/01-responsive-web-design/learn-css-colors-by-building-a-color-markers-set/step-004.md
+++ b/curriculum/challenges/english/01-responsive-web-design/learn-css-colors-by-building-a-color-markers-set/step-004.md
@@ -30,7 +30,7 @@ Your `meta` element should have a `charset` attribute set to `utf-8`.
 
 ```js
 const meta = [...document.querySelectorAll('meta')];
-const target = meta?.find(m => m?.getAttribute('charset').toLowerCase() === 'utf-8');
+const target = meta?.find(m => m?.getAttribute('charset')?.toLowerCase() === 'utf-8');
 assert.exists(target);
 ```