[Bug] : In mobile screen need to highlight Color of text in navbar

[harshal050]

In mobile screen need to highlight Color of text in navbar

issue fix:#327

Steps :

1 : open site in mobile screen
2 : go to https://nightwatchjs.org/
3 : click on 3line of navbar
4 : hover any button like 'api' you will see that it not response
5 : Fix this using add color when it hover