Hello I have an issue with my view fieldOverview.php I have a view fields.php which has link to other view

<a href="/fieldOverview/<?= $field->getId(); ?>" class="field-options" >
                        Past actions and notes
</a>

when user clicks on this link he is correctly redirected but the css doesn't load

however when i will go to http://localhost:8080/fieldOverview instead of http://localhost:8080/fieldOverview/IDNUMBER

the css styles works properly. Even though both times it goes through this function

public function fieldOverview($id){
    //$field = $this->fieldRepository->findFieldById($id);
    return $this->render('fieldOverview');
}

my render function

protected function render(string $template = null, array $variables=[]){
    $templatePath = 'public/views/'. $template.'.php';
    $output = 'File not found';

    if (file_exists($templatePath)){
        extract($variables);

        ob_start();
        include $templatePath;
        $output = ob_get_clean();
    }

    print $output;
}

maybe to make it more clear this is my index.php

require 'Routing.php';
$path = trim($_SERVER['REQUEST_URI'], '/');
$path = parse_url($path, PHP_URL_PATH);

Router::get('', 'DefaultController');
Router::get('fields', 'FieldController');
Router::get('fieldOverview', 'FieldController');

Router::run($path);

and my Routing.php

class Router {

    public static $routes;
    private static $controller;

    public static function get($url, $view) {
        self::$routes[$url] = $view;
    }

    public static function post($url, $view) {
        self::$routes[$url] = $view;
    }

    public static function run ($url) {

        $urlParts = explode("/", $url);
        $action = $urlParts[0];

        if (!array_key_exists($action, self::$routes)) {
            die("Wrong url!");
        }

        if(session_status() !== PHP_SESSION_ACTIVE){
            session_start();
        }

        if ((!isset($_COOKIE['user']) || !isset($_SESSION['logged_in_user_account_id'])
                || !isset($_SESSION['logged_in_personal_data_id']))
            && ( $action !== 'signUp' && $action !== 'login')){
            self::$controller = self::$routes['login'];
            $action = 'login';
        }else{
            self::$controller = self::$routes[$action];
        }

        $object = new self::$controller;
        $action = $action ?: 'index';

        if (isset($urlParts[1])){
            $id = intval($urlParts[1]);
        }else{
            $id ='';
        }

        $object->$action($id);
    }
}