Several Item Lightbox Fixes

-Lightbox is between top and bottom music-video-page headers. (On
mobile, it is underneath the top header, taking up full page.)
-No left and right grey areas on lightbox.
-Basic animation on expanding item's lightbox image max or min size
(although JS transition doesn't work for first click?? Also doesn't work
on mobile too well)
-Item loading dynamic (ID's for every page, will load item-1.html,
item-2.html etc...
-Static coded in; first thumbnail of Look's other items to the right of
main lightbox on PC.