un-hardcode @grid-gutter-width in @container-* LESS vars

diff --git a/less/variables.less b/less/variables.less
index ddfeae7279f2356d104f3b88bdd1ffa7458fd271..c3eeaaebc732ea75a8a79011f0c9a5a316952ca0 100644 (file)
--- a/less/variables.less
+++ b/less/variables.less
@@ -600,10 +600,10 @@
 // --------------------------------------------------
 
 // Small screen / tablet
-@container-tablet:          750px; // 720px + 30px left/right padding
+@container-tablet:          ((720px + @grid-gutter-width));
 
 // Medium screen / desktop
-@container-desktop:         970px; // 940px + 30px left/right padding
+@container-desktop:         ((940px + @grid-gutter-width));
 
 // Large screen / wide desktop
-@container-large-desktop:   1170px; // 1140px + 30px left/right padding
+@container-large-desktop:   ((1140px + @grid-gutter-width));