JSFiddle - React, Tailwind, and code Playground
HTML
<link rel="stylesheet" href="https://bootswatch.com/cosmo/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<div class="form-group">
<select id=form-default name="Form1" class="form-control" >
<option value="0">Form1</option>
<option value="1">Option2</option>
<option value="2">Option3</option>
</select>
<select id=form-green name="Form2" class="form-control" >
<option value="0">Form2</option>
<option value="1">Option2</option>
<option value="2">Option3</option>
</select>
</div>
CSS
#form-default {
margin-top:50px;
width:300px;
}
#form-green {
border:1px solid #000000;
margin-top:50px;
width:300px;
}
.form-control:focus {
border-color: #FF0000;
box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 8px rgba(255, 0, 0, 0.6);
}