Reply To: Change Notification bar text and background color

Try to add the following code snippet to the Custom CSS area in Theme Settings to do this

body .woocommerce-cart-notice {
    background-color: #459647;
}

body.woocommerce-checkout .woocommerce>.woocommerce-info .amount {
    color:#26ba45;
}

body.woocommerce-checkout .woocommerce>.woocommerce-info .button {
    color:#26ba45;
    border-color:#26ba45;
}