You can add the form-control class to the textarea element.
Example here
<div class="form-group has-error"> <textarea class="form-control"></textarea> </div>
The selector used for this is .has-error .form-control . Here is the default style:
.has-error .form-control { border-color: #a94442; -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.075); box-shadow: inset 0 1px 1px rgba(0,0,0,.075); }
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