bootstrap-responsive.css

.hidden {
  display: none;
  visibility: hidden;
}
@media (max-width: 480px) {
  .page-header h1 small {
    display: block;
    line-height: 18px;
  }
  .form-horizontal .control-group > label {
    float: none;
    width: auto;
    padding-top: 0;
    text-align: left;
  }
  .form-horizontal .controls {
    margin-left: 0;
  }
  .form-horizontal .control-list {
    padding-top: 0;
  }
  .form-horizontal .form-actions {
    padding-left: 0;
  }
  .modal {
    position: absolute;
    top: 10px;
    left: 10px;
    right: 10px;
    width: auto;
    margin: 0;
  }
  .modal.fade.in {
    top: auto;
  }
  .modal-header .close {
    padding: 10px;
    margin: -10px;
  }
}
@media (max-width: 768px) {
  .container {
    width: auto;
    padding: 0 20px;
  }
  .row {
    margin-left: 0;
  }
  .row > [class*="span"] {
    float: none;
    display: block;
    width: auto;
    margin: 0;
  }
}
@media (min-width: 768px) and (max-width: 940px) {
  .container {
    width: 748px;
    padding-left: 10px;
    padding-right: 10px;
  }
  .span1 {
    width: 44px;
  }
  .span2 {
    width: 108px;
  }
  .span3 {
    width: 172px;
  }