diff --git a/Plugin.php b/Plugin.php
index 585c28e..53e49f2 100644
--- a/Plugin.php
+++ b/Plugin.php
@@ -225,13 +225,15 @@ class MenuTree_Plugin implements Typecho_Plugin_Interface {
         $html = '<div class="in-page-preview-buttons in-page-preview-buttons-full-reader"><svg data-toggle="dropdown" aria-expanded="false" class="dropdown-toggle icon-list" version="1.1" id="tree_nav" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" viewBox="104.5 -245.5 51 51" style="enable-background:new 104.5 -245.5 50 50;" xml:space="preserve"><path d="M130.895-218.312c-0.922,0-1.842-0.317-2.59-0.951l-11.01-9.352c-1.684-1.43-1.889-3.955-0.459-5.638c1.43-1.684,3.953-1.89,5.639-0.459l8.42,7.152l8.42-7.152c1.686-1.43,4.211-1.225,5.639,0.459c1.43,1.684,1.225,4.208-0.459,5.638l-11.01,9.352C132.738-218.628,131.816-218.312,130.895-218.312z M133.486-206.289l11.008-9.352c1.684-1.43,1.889-3.955,0.459-5.638c-1.43-1.682-3.955-1.89-5.639-0.458l-8.418,7.152l-8.422-7.152c-1.686-1.431-4.209-1.225-5.639,0.459c-1.43,1.684-1.225,4.208,0.461,5.638l11.012,9.352c0.746,0.634,1.668,0.951,2.588,0.951C131.818-205.337,132.74-205.654,133.486-206.289z"/></svg><div class="dropdown-menu theme pull-right theme-white keep-open" id="toc-list"><h3>内容目录</h3><hr><div class="table-of-contents"><div class="toc"><ul><li>'. self::buildMenuHtml( self::$tree ) .'</div></div></div></li></ul></div>';
         $js = Helper::options()->pluginUrl . '/MenuTree/dropdown.js?v=' . self::$v;
         echo <<<HTML
-            <script src="{$js}"></script>
-            <script type="text/javascript">
-            jQuery('body').append('$html');
-            jQuery('.in-page-preview-buttons .dropdown-menu.keep-open').on('click', function (e) {
+        <script src="{$js}"></script>
+        <script type="text/javascript">
+        (function($) {
+            $('body').append('$html');
+            $('.in-page-preview-buttons .dropdown-menu.keep-open').on('click', function (e) {
               e.stopPropagation();
             });
-            </script>
+        })(jQuery);
+        </script>
 HTML;
         self::$id = 1;
         self::$tree = array();
