JSFiddle - React, Tailwind, and code Playground
by Edgar Martinez
HTML
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css">
<div class="form-group has-danger">
<label class="form-control-label" for="inputDanger1">Input with danger</label>
<input type="text" class="form-control form-control-danger" id="inputDanger1">
<div class="form-control-feedback">Sorry, that username's taken. Try another?</div>
<small class="form-text text-muted">Example help text that remains unchanged.</small>
</div>
<div class="input-group has-danger">
<span class="input-group-text"><i class="glyphicon glyphicon-user"></i></span>
<input type="text" class="form-control" name="txtNombre" id="txtNombre" placeholder="Nombre completo">
</div>