Craft CMS general.php using .env files

general.php

<?php

return [
    'allowAutoUpdates'       => getenv('CRAFT_ENVIRONMENT') === 'development',
    'devMode'                => getenv('CRAFT_ENVIRONMENT') === 'development',
    'environmentVariables'   => [
        'env'                 => getenv('CRAFT_ENVIRONMENT'),
        'siteUrl'             => getenv('CRAFT_SITE_URL'),
    ],
];