tool to find code syntax in files

[Aditya Kumar]

Is there a tool to find a code syntax by running a search query within a folder which contains a lot of code files?

Like I wanted to edit a css / html file from the code base - now I am not able to locate that file. 

I am on a mac - if a program is there which helps sift through all the files and search for that string which I need to work with or change that would be helpful

[rushabh]

Its called "grep". 

Please consider other members' time and post ERPNext related queries on this forum. There are many other forums for asking such queries.