Optimize styling for small devices

The original view:
![Webdesign Joomla Agentur aus Hamburg - Administration - Global Configuration - Mozilla Firefox 29 03 2013 100847](https://f.cloud.github.com/assets/1765163/316978/5fc2bc72-9850-11e2-89f4-d8eaa511ded4.jpg)
Optimized view:
![Webdesign Joomla Agentur aus Hamburg - Administration - Global Configuration - Mozilla Firefox 29 03 2013 100951](https://f.cloud.github.com/assets/1765163/316979/80cff042-9850-11e2-80e5-eb80406e3946.jpg)