Fix tag background colour on podcast tone

Before: 
![screen shot 2014-10-22 at 17 20 23](https://cloud.githubusercontent.com/assets/813383/4739825/996c2998-5a07-11e4-96ef-9abd796273d3.png)

After: 
![screen shot 2014-10-22 at 17 20 32](https://cloud.githubusercontent.com/assets/813383/4739827/9e6155cc-5a07-11e4-8d70-2b352f3a83af.png)