Documentation:
Image Box

Here you control how the image looks in the image box. There are separate settings for desktop, tablet, and phone.

Size

Here you can set a custom size for the image. The percentage value represents the image width as a proportion of the image box width.

Example: 100% will make the image the same width as the image box, while 50% will make the image half the width of the image box.

Position X / Position Y

Here you can set the horizontal and vertical position of the image within the image box.

Rotation

Here you can set the rotation of the image within the image box.

Flip

Here you can choose to flip the image within the image box.

See here for an example.