The problem with the options property.panelMaxMapArea
https://tech.yandex.ru/maps/doc/jsapi/2.1/ref/reference/Balloon-docpage/#param-options.panelMaxMapArea
How do I specify the size of the map, so the balloon
in the form of a panel was only if the map width is less than 480px?
Seems, documentation contains inaccuracy description, just use setter for options properties, something like this:
balloon.options.set('panelMaxMapArea', 480);
balloon.options.set('closeButton', false);
// and etc...