How to customize look of contact form 7??

I found one other topic on this matter, but it was a year old and I think that may be contributing to the fact I could not get it to work for me? I don’t know…

I would like to remove the shadows on my text fields, so the yare just plain borders. And I would like to make the send button match, just a simple border with the text inside – much like this example:

http://www.papermoustache.com/contact-us/

What should I do to make these modifications?