This functionality allows you to set the size of external container.
You can reduce the size of the container with image and possible advertising by putting ad units closer to images and, at the same time, moving them away from scroll arrows.
In such a way, you can do both things: make the plugin look more attractive and significantly increase click-through rate of ad units.
To be set in %, vw, px. Optimum value: 90-95%.
