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yii-bootstrap2 / bootstrap / vendors / bootstrap / less / utilities.less

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// UTILITY CLASSES
// ---------------

// Quick floats
.pull-right {
  float: right;
}
.pull-left {
  float: left;
}

// Toggling content
.hide {
  display: none;
}
.show {
  display: block;
}

// Visibility
.invisible {
  visibility: hidden;
}