I have the latest version of SpecFlow installed, and still the feature files display uncoloured, like so...
(Not enough rep to insert images)
Specflow uncoloured feature files
Is there certain configurations that are set for colours to be displayed in Specflow files?
VS2015 Specflow 2.1
There is an option for coloring syntax in Tools->Options->SpecFlow that could cause the problem.
EDIT:
Ensure your SpecFlow extension is installed correctly:
Go to Tools->Extensions and updates -> Installed look for SpecFlow for Visual Studio 2015. You might try to uninstall and install it again.
If you can't find in the list then select Online, in search type specflow, then select result and install.