diff --git a/less/_01b-base.less b/less/_01b-base.less
index a6c9c6a..40fad69 100644
--- a/less/_01b-base.less
+++ b/less/_01b-base.less
@@ -169,7 +169,7 @@ var {
 /* ----------------------------- */
 
 /* hidden but not for an assistive technology like a screen reader, Yahoo! method */
-.@{kna-namespace}visually-hidden {
+.visually-hidden {
   position: absolute !important;
   border: 0 !important;
   height: 1px !important;
diff --git a/less/_02-layout.less b/less/_02-layout.less
index a07acfb..f36f681 100644
--- a/less/_02-layout.less
+++ b/less/_02-layout.less
@@ -3,19 +3,20 @@
 /* ----------------------------- */
 
 /* module, gains superpower "BFC" Block Formating Context */
-.@{kna-namespace}mod {
+.@{kna-namespace}mod,
+.@{kna-namespace}bfc {
   overflow: hidden;
 }
 
 /* blocks that needs to be placed under floats */
-.@{kna-namespace}clear,
+.clear,
 .@{kna-namespace}line,
 .@{kna-namespace}row {
   clear: both;
 }
 
 /* blocks that must contain floats */
-.@{kna-namespace}clearfix,
+.clearfix,
 .@{kna-namespace}line {
   &::after {
     content: "";
diff --git a/sass/_01b-base.scss b/sass/_01b-base.scss
index f37f297..4918eac 100644
--- a/sass/_01b-base.scss
+++ b/sass/_01b-base.scss
@@ -163,7 +163,7 @@ var {
 /* ----------------------------- */
 
 /* hidden but not for assistance tools, Yahoo! method */
-.#{$kna-namespace}visually-hidden {
+.visually-hidden {
   position: absolute !important;
   border: 0 !important;
   height: 1px !important;
diff --git a/sass/_02-layout.scss b/sass/_02-layout.scss
index 479b807..e48c332 100644
--- a/sass/_02-layout.scss
+++ b/sass/_02-layout.scss
@@ -3,19 +3,20 @@
 /* ----------------------------- */
 
 /* module, gains superpower "BFC" Block Formating Context */
-.#{$kna-namespace}mod {
+.#{$kna-namespace}mod,
+.#{$kna-namespace}bfc {
   overflow: hidden;
 }
 
 /* blocks that needs to be placed under floats */
-.#{$kna-namespace}clear,
+.clear,
 .#{$kna-namespace}line,
 .#{$kna-namespace}row {
   clear: both;
 }
 
 /* blocks that must contain floats */
-.#{$kna-namespace}clearfix,
+.clearfix,
 .#{$kna-namespace}line {
   &::after {
     content: "";