[twitter-bootstrap] Bootstrap: wider input field

in bootstrap 3.0 :

Set heights using classes like .input-lg, and set widths using grid column classes like .col-lg-*.

Example:

<div class="row">
    <div class="col-xs-2">
        <input type="text" class="form-control" placeholder=".col-xs-2">
    </div>
    <div class="col-xs-3">
        <input type="text" class="form-control" placeholder=".col-xs-3">
    </div>
    <div class="col-xs-4">
        <input type="text" class="form-control" placeholder=".col-xs-4">
    </div>
</div>

Source: http://getbootstrap.com/css/#forms-control-sizes