diff --git a/_data/tabs.yml b/_data/tabs.yml
index f2fa30e8d37d4ea63e6e7f8a263222cee251ed96..72193ec3564a7179ba63392d053958b73c00509a 100644
--- a/_data/tabs.yml
+++ b/_data/tabs.yml
@@ -4,9 +4,9 @@
 - name: Kernel
   link: /html/kernel.html
   id  : kernel
-- name: GUI
-  link: /html/gui.html
-  id  : gui
 - name: Specification
   link: /html/acsl.html
   id  : acsl
+- name: GUI
+  link: /html/gui.html
+  id  : gui