More gallery endslate styling fixes

Fixes issues  @paperboyo mentioned in #7087 

- remove legacy css
- fix borders
- change class names to match new facia styles

/cc @mattosborn

![google chrome](https://cloud.githubusercontent.com/assets/80089/5027254/b3e17a52-6b24-11e4-81b4-12cadcefccea.png)