diff --git a/src/app/layout/Header.tsx b/src/app/layout/Header.tsx
index 42c209b..3f95ee6 100644
--- a/src/app/layout/Header.tsx
+++ b/src/app/layout/Header.tsx
@@ -146,7 +146,7 @@ export default function Header() {
         background: scrolled ? 'rgba(255,255,255,0.88)' : T.paper,
         backdropFilter: scrolled ? 'blur(18px) saturate(160%)' : 'none',
         WebkitBackdropFilter: scrolled ? 'blur(18px) saturate(160%)' : 'none',
-        borderBottom: scrolled ? '1px solid rgba(7,29,73,0.10)' : '1px solid transparent',
+        borderBottom: scrolled ? '1px solid rgba(7,29,73,0.10)' : 'none',
         direction:  lang === 'fa' ? 'rtl' : 'ltr',
         transition: 'background 220ms ease, backdrop-filter 220ms ease, border-color 220ms ease',
       }}