UX: fix typo in lazyYT.css

For some reason my previous PR https://github.com/tylerpearson/lazyYT/pull/10 had wrong padding (twice as big).
Fixing it now so that it will look like [expected](https://cloud.githubusercontent.com/assets/157609/4379156/3104408a-435e-11e4-99c0-fb5a6616ec53.png).

My apologies.