为什么在JS中找不到admin url？

// config.js
export const ADMIN_URL = process.env.ADMIN_URL || 'http://default-admin-url.com';

# .env.development
ADMIN_URL=http://dev-admin-url.com

# .env.production
ADMIN_URL=http://prod-admin-url.com

if (user.isAdmin) {
    window.location.href = ADMIN_URL;
} else {
    alert('You do not have permission to access the admin page.');
}

console.log('Admin URL:', ADMIN_URL);

// config.js
export const ADMIN_URL = process.env.ADMIN_URL || 'http://default-admin-url.com';

// main.js
import { ADMIN_URL } from './config.js';

document.getElementById('admin-link').addEventListener('click', () => {
    if (user.isAdmin) {
        window.location.href = ADMIN_URL;
    } else {
        alert('You do not have permission to access the admin page.');
    }
});