diff --git a/index.php b/index.php
index 79e48b0..86c82c3 100644
--- a/index.php
+++ b/index.php
@@ -7,6 +7,13 @@ if (!is_dir(__DIR__ . "/cache")) mkdir(__DIR__ . "/cache", 0775, true);
 function h($s){ return htmlspecialchars((string)$s, ENT_QUOTES, "UTF-8"); }
 function nice_title($s){ return trim(ucwords(str_replace(['_','-'], ' ', (string)$s))); }
 function lower_text($s){ return function_exists('mb_strtolower') ? mb_strtolower((string)$s, 'UTF-8') : strtolower((string)$s); }
+function ci_contains($haystack, $needle){
+    $haystack = (string)$haystack;
+    $needle = (string)$needle;
+    if ($needle === '') return true;
+    if (function_exists('mb_stripos')) return mb_stripos($haystack, $needle, 0, 'UTF-8') !== false;
+    return strpos(lower_text($haystack), lower_text($needle)) !== false;
+}
 function keep_non_empty(array $params): array { return array_filter($params, fn($v)=>$v !== '' && $v !== null); }
 function query_url(array $params): string {
     $params = keep_non_empty($params);
@@ -164,13 +171,13 @@ $videos = array_values(array_filter($videos, function($v) use ($videoCache, $key
     $location = (string)($m['location'] ?? '');
 
     if ($keywordType === 'date') {
-        return stripos($date, $keywordValue) !== false || stripos($sortDate, $keywordValue) !== false;
+        return ci_contains($date, $keywordValue) || ci_contains($sortDate, $keywordValue);
     }
     if ($keywordType === 'location') {
-        return stripos($location, $keywordValue) !== false;
+        return ci_contains($location, $keywordValue);
     }
 
-    return stripos($title, $keywordValue) !== false || stripos($description, $keywordValue) !== false;
+    return ci_contains($title, $keywordValue) || ci_contains($description, $keywordValue);
 }));
 
 $page = max(1, (int)($_GET['page'] ?? 1));
diff --git a/new.php b/new.php
index a23d10b..41f1f22 100644
--- a/new.php
+++ b/new.php
@@ -7,6 +7,14 @@ if (!is_dir(__DIR__ . "/cache")) mkdir(__DIR__ . "/cache", 0775, true);
 const ARTICLE_ID_FILE = '.mvlog-id';
 function h($s){ return htmlspecialchars((string)$s, ENT_QUOTES, "UTF-8"); }
 function ajax_json($data){ header('Content-Type: application/json; charset=UTF-8'); echo json_encode($data, JSON_UNESCAPED_UNICODE); exit; }
+function lower_text($s){ return function_exists('mb_strtolower') ? mb_strtolower((string)$s, 'UTF-8') : strtolower((string)$s); }
+function ci_contains($haystack, $needle){
+    $haystack = (string)$haystack;
+    $needle = (string)$needle;
+    if ($needle === '') return true;
+    if (function_exists('mb_stripos')) return mb_stripos($haystack, $needle, 0, 'UTF-8') !== false;
+    return strpos(lower_text($haystack), lower_text($needle)) !== false;
+}
 function ascii_safe($s){
     $s = strtr((string)$s, [
         'æ'=>'ae','Æ'=>'Ae','ø'=>'o','Ø'=>'O','å'=>'aa','Å'=>'Aa',
@@ -845,9 +853,9 @@ if ($keywordValue !== '' || $statusFilterActive) {
         $date = (string)($meta['date'] ?? ($data['date'] ?? ''));
         $location = (string)($meta['location'] ?? ($data['place'] ?? ''));
 
-        if ($keywordType === 'date') return stripos($date, $keywordValue) !== false;
-        if ($keywordType === 'location') return stripos($location, $keywordValue) !== false;
-        return stripos($title, $keywordValue) !== false || stripos($description, $keywordValue) !== false;
+        if ($keywordType === 'date') return ci_contains($date, $keywordValue);
+        if ($keywordType === 'location') return ci_contains($location, $keywordValue);
+        return ci_contains($title, $keywordValue) || ci_contains($description, $keywordValue);
     }));
 }