diff --git a/docs/assets/css/bootstrap-responsive.css b/docs/assets/css/bootstrap-responsive.css
index f8077aa1fb07..9259d26dca91 100644
--- a/docs/assets/css/bootstrap-responsive.css
+++ b/docs/assets/css/bootstrap-responsive.css
@@ -817,8 +817,11 @@
   .row-fluid [class*="span"] {
     display: block;
     float: none;
-    width: auto;
+    width: 100%;
     margin-left: 0;
+    -webkit-box-sizing: border-box;
+       -moz-box-sizing: border-box;
+            box-sizing: border-box;
   }
   .span12,
   .row-fluid .span12 {
diff --git a/less/responsive-767px-max.less b/less/responsive-767px-max.less
index eebecb8e4a22..79c7eaa82b86 100644
--- a/less/responsive-767px-max.less
+++ b/less/responsive-767px-max.less
@@ -61,8 +61,9 @@
   .row-fluid [class*="span"] {
     float: none;
     display: block;
-    width: auto;
+    width: 100%;
     margin-left: 0;
+    .box-sizing(border-box);
   }
   .span12,
   .row-fluid .span12 {