Fix #162: Inherit wrapper height from page area
As the wrapper div is needed for overflow events and we couldn't remove it in !143 (closed) this does the next best thing and sets a height for the wrapper which it inherits from the page area.
As the wrapper div is needed for overflow events and we couldn't remove it in !143 (closed) this does the next best thing and sets a height for the wrapper which it inherits from the page area.