diff --git a/src/components/Header.jsx b/src/components/Header.jsx
index 57642db..dccd188 100644
--- a/src/components/Header.jsx
+++ b/src/components/Header.jsx
@@ -84,7 +84,7 @@ export default function Header(props) {
   const [mobileMenuOpen, setMobileMenuOpen] = useState(false)
 
   const pathname = props.url.pathname
-  const currentLocale = props.locale || 'en'
+  const currentLocale = props.locale || defaultLocale
   const t = nav[currentLocale] || nav.en
 
   function langUrl(code) {
@@ -164,7 +164,7 @@ export default function Header(props) {
 
   const pathSegments = pathname.slice(1).split('/')
   const activeSegment =
-    currentLocale !== 'en' ? pathSegments[1] : pathSegments[0]
+    currentLocale !== defaultLocale ? pathSegments[1] : pathSegments[0]
 
   /* ── Shared class fragments ─────────────────────────────────────────────── */
   const linkBase =