whmcsCrosterTemplates/thurdata/css/TelephoneCountryCodeDropdown.css

/**
 * WHMCS Telephone Country Code Dropdown
 *
 * Using https://github.com/jackocnr/intl-tel-input
 *
 * @copyright Copyright (c) WHMCS Limited 2005-2017
 * @license http://www.whmcs.com/license/ WHMCS Eula
 */

.intl-tel-input {
    width: 100%;
}