<link href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<div class="date">
<select name="countryCode" id="">
<option data-countryCode="GB" value="44" Selected>UK (+44)</option>
<option data-countryCode="US" value="1">USA (+1)</option>
<optgroup label="Other countries">
<option data-countryCode="DZ" value="213">Algeria (+213)</option>
<option data-countryCode="AD" value="376">Andorra (+376)</option>
<option data-countryCode="AO" value="244">Angola (+244)</option>
<option data-countryCode="AI" value="1264">Anguilla (+1264)</option>
<option data-countryCode="AG" value="1268">Antigua & Barbuda (+1268)</option>
<option data-countryCode="ZW" value="263">Zimbabwe (+263)</option>
</optgroup>
</select>
</div>
