diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..5f15df4
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "styl/vendor/flexbox-stylus"]
+	path = styl/vendor/flexbox-stylus
+	url = git@github.com:psa-acariou/flexbox-stylus.git
diff --git a/styl/grids/_grillade.styl b/styl/grids/_grillade.styl
index ea65fce..bdd4c6f 100644
--- a/styl/grids/_grillade.styl
+++ b/styl/grids/_grillade.styl
@@ -1,6 +1,7 @@
 /* ---------------------------------- */
 /* ==Grillade : Simple Grid System    */
 /* ---------------------------------- */
+@import '../vendor/flexbox-stylus/stylus/flexbox.styl'
 /* Doc : http://grillade.knacss.com */
 // gutter values for grid layouts. Unit can be: %, px, em, rem
 grid-gutters = { '': 1rem, '-l': 2rem, '-xl': 4rem }
@@ -8,12 +9,6 @@ grid-gutters = { '': 1rem, '-l': 2rem, '-xl': 4rem }
 // https://github.com/alsacreations/KNACSS/issues/133;
 iefix = 0.01px
 
-tiny         = 543px
-small        = 767px
-medium       = 991px
-large        = 1199px
-extra-large  = 1439px
-
 @media (min-width: tiny + 1)
   [class*=" grid-"]
   [class^="grid-"]
diff --git a/styl/vendor/flexbox-stylus b/styl/vendor/flexbox-stylus
new file mode 160000
index 0000000..b060889
--- /dev/null
+++ b/styl/vendor/flexbox-stylus
@@ -0,0 +1 @@
+Subproject commit b060889b8100e9f2d69ffc69b4da368d1a40f297