Audio page tweaks

 * min height of content
 * colour of comment counts
 * padding on dark background containers

![screen shot 2014-10-01 at 14 38 40](https://cloud.githubusercontent.com/assets/74132/4475822/65c71190-4970-11e4-885f-292977612952.png)

Is this a magic number? Other than that :+1: