Close button position fix

The position of cross used to close the modal is down its natural position (floating elements need to be positioned before contents).

![schermata 2014-06-11 alle 12 23 13](https://cloud.githubusercontent.com/assets/1561134/3243020/8a9fadcc-f152-11e3-92be-77faf64c6d12.png)

Problem [here](http://jsbin.com/indrimuska/119/edit) and solution [here](http://jsbin.com/indrimuska/120/edit).