本句为倒装句,介词短语作状语 修饰Only there.
正常语序是You can only see all of the nice things at the top there.我的意思是，本句Only there can you see all of the nice things，这样的表达也是对的，但是Only there后面加了at the top，那at the top是补充only there的补语还是状语？应该是补充only there吧