No worries, I worked it out in the end!
For anyone else looking to solve this, this is the CSS I used –
div.wpcf7 input[type=”submit”], input[type=”button”], input[type=”reset”] {
width: 80px;
background: #EC3E73;
background: linear-gradient none;
border: 2px solid #EC3E73;
color: #fff;
font-size: 15px;
font-family: ‘Maven Pro’, sans-serif;
}