mm on "[Plugin: Contact Form 7] Contact form 7: How to style "choose file" button?"

Hello,

I have previously restyled the contact button which worked fine.
But I am not sure how to style the "choose file button".

I suppose it should look like something like this:

.contact-submit input {
	width: 100px;
	height: 30px;
	background-color: #999999;
	font-size: 13px;
	color: #fff;
	border: 1px solid #fff;
	border-radius: 7px;
}

But I am not sure how to name it...

An idea?

Thank you for having a look

http://wordpress.org/extend/plugins/contact-form-7/