Can’t Change Button Color

I made the mistake of applying a style kit in the Inpirio Pro theme and now my buttons are the wrong color and I can’t seem to revert the changes or change the button color. I have even tried additional css below, no luck. If anyone knows how to fix the button color or revert the style kit, I would appreciate the assist. I want the button background to be black.

wp-block-button .wp-block-button__link {
color: #fff;
font-size: 18px;
border: 2px solid #0bb4aa;
background-color: transparent;
}

.wp-block-button .wp-block-button__link:hover {
border-color: #000000;
background: #000000;
color: #fff;
}