fix the font colours, weight and size.

The puzzle `125-570a9ed4` from #125 has to be resolved:

https://github.com/ammaratef45/zold-flutter-client/blob/495cc38a06684c8d5ad5725ad67a5e376dec5ff3/zold_wallet/lib/home_page/home_page_view.dart#L14-L14

The puzzle was created by Ammar Atef on 11-Jul-19.

role: DEV.

If you have any technical questions, don't ask me, submit new tickets instead. The task will be \"done\" when the problem is fixed and the text of the puzzle is _removed_ from the source code. Here is more about [PDD](http://www.yegor256.com/2009/03/04/pdd.html) and [about me](http://www.yegor256.com/2017/04/05/pdd-in-action.html).