Changing color of one button?

Site URL: https://www.siftbakeshopmystic.com/reservations

I want to change the color of the "Mix Reservations" button to order to match the branding for the restaurant located above the bakery. How can I change just the one button to orange?

13 hours ago, esparks_sift said:

Site URL: https://www.siftbakeshopmystic.com/reservations

I want to change the color of the "Mix Reservations" button to order to match the branding for the restaurant located above the bakery. How can I change just the one button to orange?

Add to Design > Custom CSS

/* Mix reservations button */
.button-block a[href*="resy.com/cities/mys/mix"] {
    background-color: #ff8138;
}