add_action( 'wp_enqueue_scripts', 'child_lookout_enqueue_styles' );
 function child_lookout_enqueue_styles() {
      wp_enqueue_style( 'parent-style', get_template_directory_uri() . '/style.css' );
      wp_enqueue_style('lookout-mobile', get_template_directory_uri() . '/style-mobile.css');
      }

// mobile stylesheet
wp_enqueue_style('lookout-mobile', get_template_directory_uri().'/style-mobile.css');

function test_dequeue_styles() {
    // this removes the original style
wp_dequeue_style( 'lookout-mobile' );
wp_deregister_style( 'lookout-mobile' );

function child_lookout_enqueue_styles() {
  wp_enqueue_style( 'parent-style', get_template_directory_uri() . '/style.css' );
  wp_enqueue_style('lookout-mobile', get_stylesheet_directory_uri() . '/style-mobile.css', array('parent-style'));
  }
add_action( 'wp_enqueue_scripts', 'child_lookout_enqueue_styles' );