<?php
declare(strict_types=1);

/**
 * [base64url_decode decode base64 url encoded data.]
 *
 * @param  string      $data   Data to decode.
 *
 * @param  boolean     $strict Strinct flag.
 *
 * @return string|bool          Decoded String.
 */
function base64url_decode(string $data, bool $strict=false) {
  $b64 = strtr($data, '-_', '+/');
  return base64_decode($b64, $strict);
}