function theme_scripts_and_css() {
    wp_deregister_script( 'jquery' ); //supprime jQuery s'il est dèjà chargé
    wp_enqueue_script( 'jquery', 'https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js');
    wp_enqueue_script( 'bootstrapjs', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js', array( 'jquery' ), false, false);
    wp_enqueue_style( 'bootstrapcss', 'https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css');
}

Zoom

add_action( 'wp_enqueue_scripts', 'theme_scripts_and_css' );