Control colours using theme

[Aditya-Sh]

There are already some some issues present with relation to this, I just want to bring some attention to this.
It'll be great to have support for themes based on primary colours and other variables. It's a much required feature now, since we usually build dynamic applications and need to change the look and feel of the app and keep most functionalities same.

Currently I want to change colour of input field, is there a way I can do that? I was not able to find any resource on that.