Lens background-image distorted

[nxaxg]

The image of the lens setted as the lens background-image seems to distort due to css classes at image to be sized.

Image seems to work properly if thus classes is removed (as well as the css properties of the class) as the image uses the real width x height of the file (overflows from red border-box line)

[nxaxg]

Ok, so, after checking issue #3 i've set the background size using the thumb.width and thumb.height

lets see how it works.