Fix bottom panel input padding on OSX

Related to #34

![screen shot 2013-12-30 at 11 20 48 pm](https://f.cloud.github.com/assets/887133/1825762/10d914f0-71d3-11e3-850f-72f55134171e.png)
![screen shot 2013-12-30 at 11 21 18 pm](https://f.cloud.github.com/assets/887133/1825763/10d996c8-71d3-11e3-9290-8d7c48660aff.png)