Use wp_enqueue_script() inside the wp_enqueue_scripts hook to load your JS file the right way.

Add this to your functions.php. In a child theme, use get_stylesheet_directory_uri() instead of get_template_directory_uri().

function lotgrafix_enqueue_scripts() {
    wp_enqueue_script(
        'lotgrafix-main',
        get_template_directory_uri() . '/js/main.js',
        array(),
        '1.0.0',
        true
    );
}
add_action( 'wp_enqueue_scripts', 'lotgrafix_enqueue_scripts' );