.wp-core-ui .button-primary {
    background: #c5396e;
    border-color: #c5396e #c5396e #c5396e;
    box-shadow: 0 1px 0 #c5396e;
    color: #fff;
    text-decoration: none;
    text-shadow: 0 -1px 1px #c5396e, 1px 0 1px #c5396e, 0 1px 1px #c5396e, -1px 0 1px #c5396e;
}

.login #login_error, .login .message, .login .success {
    border-left: 4px solid #c5396e;
}