select box related js

by lemon kazi

HTML

<select name="firstbox" id="firstbox" style="width: 100px;">
    <option disabled selected>Select Region</option>
    <option value="europe">Europe</option>
    <option value="north_america">North America</option>
    <option value="latam">Latam</option>
		<option value="middleast_africa">middleast_africa</option>
</select>
<div id="select_boxes">
	<select name="secondbox" id="secondbox" style="width: 100px;">
		<option value="">Select</option>
	</select>
</div>


<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

JavaScript

var default_values = {
    "europe": {"label": "first","values": ['Russia','Ukraine','France','Spain','Sweden','Norway','Germany','Finland','Poland','Italy','United Kingdom','Romania','Belarus','Kazakhstan','Greece','Bulgari','Iceland','Hungary','Portugal','Austria','Czechia','Serbia','Ireland','Lithuania','Latvia','Croatia','Bosnia and Herzegovina','Slovakia','Estonia','Denmark','Switzerland','Netherlands','Moldova','Belgium','Armenia','Albania','North Macedonia','Turkey','Slovenia','Montenegro','Kosovo','Azerbaijan','Cyprus','Luxembourg+','Georgia','Andorra','Malta','Liechtenstein','San Marino','Monaco','Vatican City']},
    "north_america": {"label": "second","values": ['Antigua and Barbuda','Bahamas','Barbados','Belize','Canada','Costa Rica','Cuba','Dominica','Dominican Republic','El Salvador','Grenada','Guatemala','Haiti','Honduras','Jamaica','Mexico','Nicaragua','Saint Kitts and Nevis','Panama','Saint Lucia','Saint Vincent and the Grenadines','Trinidad and Tobago','United States of America']},
    "latam": {"label": "third","values": ['Belize','Costa Rica','El Salvador','Guatemala','Honduras','Mexico','Nicaragua','Panama','Argentina','Bolivia','Brazil','Chile','Colombia','Ecuador','French Guiana','Guyana','Paraguay','Peru','Suriname','Uruguay','Venezuela','Cuba','Dominican Republic','Haiti','Guadeloupe','Martinique','Puerto Rico','Saint-Barthélemy','Saint-Martin']},
		 "middleast_africa": {"label": "third","values": ['Nigeria','Ethiopia','Egypt','DR Congo','Tanzania','South Africa','Kenya','Uganda','Algeria','Sudan','Morocco','Angola','Mozambique','Ghana','Madagascar','Cameroon','Côte dIvoire','Niger','Burkina Faso','Mali','Malawi','Zambia','Senegal','Chad','Somalia','Guinea','Zimbabwe','Guinea','Rwanda','Benin','Burundi','Tunisia','South Sudan','Togo','Sierra Leone','Libya','Congo','Liberia','Central African Republic','Mauritania','Eritrea','Namibia','Gambia','Botswana','Gabon','Lesotho','Guinea-Bissau','Equatorial...