css - rails bootstrap missing classes -

i use rails 4 , bootstrap 3 , has basic classes many of them missing. gemfile

...         gem "therubyracer"      gem "less-rails" #sprockets (what rails 3.1 uses asset pipeline) supports less      gem "twitter-bootstrap-rails" ... 

my application.css

 *= require bootstrap_and_overrides   *= require_self  *= require_tree 

my application has basic styles forms , buttons there no many classes col-xs-6 col-md-4 can't build grid layout.

when put example code bootstrap site view

<div class="row">   <div class="col-xs-12 col-md-8">.col-xs-12 .col-md-8</div>   <div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div> </div>  <!-- columns start @ 50% wide on mobile , bump 33.3% wide on desktop --> <div class="row">   <div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>   <div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div>   <div class="col-xs-6 col-md-4">.col-xs-6 .col-md-4</div> </div>  <!-- columns 50% wide, on mobile , desktop --> <div class="row">   <div class="col-xs-6">.col-xs-6</div>   <div class="col-xs-6">.col-xs-6</div> </div> 

i've got this

.col-xs-12 .col-md-8 .col-xs-6 .col-md-4 .col-xs-6 .col-md-4 .col-xs-6 .col-md-4 .col-xs-6 .col-md-4 .col-xs-6 .col-xs-6 

if check issues twitter-bootstrap-rails, you'll see frequently raised issue master branch bootstrap 2.3.2, i.e. (the now-unsupported) bootstrap 2 rather bootstrap 3. , isn't mentioned in readme. example grid markup bootstrap 3, won't work -- grid system changed between bootstrap 2 , bootstrap 3.

to make work, you'll either have stick bootstrap 2 markup, or try luck bootstrap 3 branch of twitter-bootstrap-rails instead.