diff --git a/views/layout_header.php b/views/layout_header.php
index caf2133..b8eb2ed 100644
--- a/views/layout_header.php
+++ b/views/layout_header.php
@@ -55,7 +55,9 @@ $_lt_assetVer  = $GLOBALS['config']['ASSET_VERSION'] ?? '20260329';
     ], JSON_UNESCAPED_UNICODE | JSON_HEX_TAG) ?>;
   </script>
 </head>
-<body class="lt-scanlines">
+<body>
+  <!-- Scanlines overlay — dedicated div avoids conflict with body::before/::after pseudo-elements -->
+  <div class="lt-scanlines" aria-hidden="true" style="position:fixed;inset:0;pointer-events:none;z-index:9998"></div>
 
   <!-- SKIP LINK -->
   <a class="lt-skip-link" href="#main-content">Skip to main content</a>
