Fixed titled check in checkbox in iPhone

Hello! I've tried to fix this issue https://github.com/FezVrasta/bootstrap-material-design/issues/24 by adding this 6 lines of code. I'm not sure about the animation of the checkbox if it is animate in the right degrees. I'm sorry if I really don't know how to modify it in LESS. Here is the screenshot.
![image](https://cloud.githubusercontent.com/assets/6078637/4332749/866251dc-3fd7-11e4-978a-20ca085b28e7.png)