WP theme file Cache busting

if ( site_url() == "http://domain.com" ) {
    define( "VERSION", time() );
} else {
    define( "VERSION", wp_get_theme()->get( "Version" ) );
}

function alpha_assets() {
    wp_enqueue_style( "alpha", get_stylesheet_uri(), null, VERSION 
    );
}
add_action( "wp_enqueue_scripts", "alpha_assets" );