Constants file in project

[rajasajidmanzoor]

Hello
I am following this tutorial.
https://www.youtube.com/watch?v=PRQCAL_RMVo
In this tutorial (at 39:05 seconds) author is using constants file.. I am not getting how to use this..

So i added constants at end of component but issue is color is not getting.

in console i can see this
color: undefined