Customizable 404 Error Pages for Specific Routes

How about defining routes for the 404 page like this?

PHP Code:

// For customized 404 page.
$routes->get('api/(:any)', 'Error404::index'); 


PHP Code:

<?php

namespace App\Controllers;

use CodeIgniter\API\ResponseTrait;
use CodeIgniter\HTTP\ResponseInterface;

class Error404 extends BaseController
{
    use ResponseTrait;

    public function index(): ResponseInterface
    {
        return $this->respond(['error' => 'API not found'], 404);
    }
} 


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