diff --git a/skin/admin.phps b/skin/admin.phps
index 559977b..a9671a0 100644
--- a/skin/admin.phps
+++ b/skin/admin.phps
@@ -150,7 +150,7 @@ return <<<HTML
     {$ctx->if_true($note_ru,
         fn() => '<div class="blog-upload-item-note"><span>Ru</span>'.$note_ru.'</div>')}
     <div class="blog-upload-item-md" id="upload{$id}_md" style="display: none">
-        <input type="text" value="{$markdown}" onclick="this.select()" readonly size="30">
+        <input type="text" value="{$markdown}" onclick="this.select()" readonly style="width: 100%">
     </div>
 </div>
 HTML;
