addComponent($box1); $row1->addComponent($box2); $row1->addComponent($box3); $row2 = new Container('flex gap-6'); $row2->addComponent($box4); $row2->addComponent($box5); $mainContainer->addComponent($row1); $mainContainer->addComponent($row2); // Set window content and run $window->setRoot($mainContainer); $app->addWindow($window); $app->run();