Never mind,
Already fixed with !important.
um input[type=submit].um-button,
.um input[type=submit].um-button:focus,
.um a.um-button,
.um a.um-button.um-disabled:hover,
.um a.um-button.um-disabled:focus,
.um a.um-button.um-disabled:active {
background: #00c3aa!important;
border-radius: 50px !important;
}
Cheers.