diff --git a/docs/assets/css/bootstrap.css b/docs/assets/css/bootstrap.css
index 01d6d23f744f635b0be95b118e521ccacb57eb55..9e1ad72e60ad3c1ba6a10a051d26998f6b215975 100644
--- a/docs/assets/css/bootstrap.css
+++ b/docs/assets/css/bootstrap.css
@@ -1178,6 +1178,11 @@ textarea:-moz-placeholder {
   color: #999999;
 }
 
+input::-moz-placeholder,
+textarea::-moz-placeholder {
+  color: #999999;
+}
+
 input:-ms-input-placeholder,
 textarea:-ms-input-placeholder {
   color: #999999;
diff --git a/less/mixins.less b/less/mixins.less
index 46241ab46bf8215ef919bbdb0eeb2e875d43871f..ad1597121785c1644b484f2e38c61c1ae388a12e 100644
--- a/less/mixins.less
+++ b/less/mixins.less
@@ -54,15 +54,10 @@
 
 // Placeholder text
 .placeholder(@color: @input-color-placeholder) {
-  &:-moz-placeholder {
-    color: @color;
-  }
-  &:-ms-input-placeholder {
-    color: @color;
-  }
-  &::-webkit-input-placeholder {
-    color: @color;
-  }
+  &:-moz-placeholder            { color: @color; } // Firefox 4-18
+  &::-moz-placeholder           { color: @color; } // Firefox 19+
+  &:-ms-input-placeholder       { color: @color; } // Internet Explorer 10+
+  &::-webkit-input-placeholder  { color: @color; } // Safari and Chrome
 }
 
 // Text overflow