.woocommerce-orders-table__cell-order-actions .invoice a,
.woocommerce-MyAccount-content a.invoice {
    background: #b1c33c !important;
    color: #fff !important;
    border-color: #b1c33c !important;
}
.woocommerce-orders-table__cell-order-actions .invoice a:hover,
.woocommerce-MyAccount-content a.invoice:hover {
    background: #9bb130 !important;
    border-color: #9bb130 !important;
}