Submit form button formatting

How do I change the background and font color of “submit” button in the contact form including the hover state? FYI this form is in a footer widget.

Here is the CSS I was using:

.custom_html-2 input.button [type=’submit’] {
width:50%!important;
background-color: #003a71!important;
color: white;
}
.custom_html-2 input.button[type=’submit’]:hover {
width:50%!important;
background-color: #00a9d8;!important;
color: white;
}