Elep

<?php if ( ! defined( 'ABSPATH' ) ) { die; } // Cannot access directly.
/**
 *
 * Field: radio
 *
 * @since 1.0.0
 * @version 1.0.0
 *
 */
if( ! class_exists( 'CSF_Field_radio' ) ) {
  class CSF_Field_radio extends CSF_Fields {

public function __construct( $field, $value = '', $unique = '', $where = '', $parent = '' ) {
      parent::__construct( $field, $value, $unique, $where, $parent );
    }

public function render() {

$args = wp_parse_args( $this->field, array(
        'inline' => false,
      ) );

$inline_class = ( $args['inline'] ) ? ' class="csf--inline-list"' : '';

echo $this->field_before();

if( isset( $this->field['options'] ) ) {

$options = $this->field['options'];
        $options = ( is_array( $options ) ) ? $options : array_filter( $this->field_data( $options ) );

if( is_array( $options ) && ! empty( $options ) ) {

echo '<ul'. $inline_class .'>';
          foreach ( $options as $option_key => $option_value ) {

if( is_array( $option_value ) && ! empty( $option_value ) ) {

echo '<li>';
              echo '<ul>';
              echo '<li><strong>'. $option_key .'</strong></li>';
              foreach( $option_value as $sub_key => $sub_value ) {
                $checked = ( $sub_key == $this->value ) ? ' checked' : '';
                echo '<li><label><input type="radio" name="'. $this->field_name() .'" value="'. $sub_key .'"'. $this->field_attributes() . $checked .'/> '. $sub_value .'</label></li>';
              }
              echo '</ul>';
              echo '</li>';

} else {

$checked = ( $option_key == $this->value ) ? ' checked' : '';
              echo '<li><label><input type="radio" name="'. $this->field_name() .'" value="'. $option_key .'"'. $this->field_attributes() . $checked .'/> '. $option_value .'</label></li>';

}

}
          echo '</ul>';

} else {

echo ( ! empty( $this->field['empty_message'] ) ) ? $this->field['empty_message'] : esc_html__( 'No data provided for this option type.', 'csf' );

}

} else {
        $label = ( isset( $this->field['label'] ) ) ? $this->field['label'] : '';
        echo '<label><input type="radio" name="'. $this->field_name() .'" value="1"'. $this->field_attributes() . checked( $this->value, 1, false ) .'/> '. $label .'</label>';
      }

echo $this->field_after();

}

}
}