diff --git a/layouts/partials/module/node/toc.html b/layouts/partials/module/node/toc.html
index 0df3d66..9d254b2 100644
--- a/layouts/partials/module/node/toc.html
+++ b/layouts/partials/module/node/toc.html
@@ -5,7 +5,7 @@
     <div class="accordion" id="accordion-{{ ($id_toc) }}">
       <div class="accordion-item">
         <h2 class="accordion-header">
-          <a class="accordion-button collapsed" href="#" role="button"
+          <a class="accordion-button collapsed" href="#" role="button" tabindex="0"
              data-bs-toggle="collapse" data-bs-target="#collapse-{{ ($id_toc) }}"
              aria-expanded="false" aria-controls="collapse-{{ ($id_toc) }}" aria-label='{{ (i18n "toc") }}'>
               {{ (i18n "toc") }}