diff --git a/templates/_base.html b/templates/_base.html
index 25d1e49..c2a7f7d 100644
--- a/templates/_base.html
+++ b/templates/_base.html
@@ -83,7 +83,9 @@
                     <div class="dropdown-menu shadow-none shadow-lg text-left text-lg-left" aria-labelledby="navbarDropdown">
                       {% for tmp_page in subsection.pages %}
                         {% if tmp_page.extra.menu_item and tmp_page.extra.menu_item == "th1" %}
-                        <a class="dropdown-item pt-2 pb-2 mx-4 mt-2 mb-2 mt-sm-3 mb-sm-3 w-auto btn btn-primary btn-inversed {% if current_path == tmp_page.path %}active{% endif %}" href="{{ tmp_page.permalink }}">{{ tmp_page.title }}</a>
+                        <a class="dropdown-item pt-2 pb-2 mx-4 mt-2 mb-2 mt-sm-3 mb-sm-3 w-auto btn btn-primary btn-inversed {% if current_path == tmp_page.path %}active{% endif %}" href="{{ tmp_page.permalink }}">
+                          <center>{{ tmp_page.title }}</center>
+                        </a>
                         {% else %}
                         <a class="dropdown-item pt-2 pb-2 {% if current_path == tmp_page.path %}active{% endif %}" href="{{ tmp_page.permalink }}">{{ tmp_page.title }}</a>
                         {% endif %}