I had the same problem. I solved it in part with the following CSS:
.widget_calendar tbody a,
.customize-support button,
.customize-support button[disabled]:focus,
.customize-support input[type=”button”],
.customize-support input[type=”button”][disabled]:focus,
.customize-support input[type=”reset”],
.customize-support input[type=”reset”][disabled]:focus,
.customize-support input[type=”submit”],
.customize-support input[type=”submit”][disabled]:focus,
.customize-support .menu-toggle.toggled-on,
.customize-support .menu-toggle.toggled-on:focus,
.customize-support .pagination:before,
.customize-support .pagination:after,
.customize-support .pagination .prev,
.customize-support .pagination .next,
.customize-support .page-links a
{
background-color: #6d3b48; color:#efddc9 };
}
.customize-support button:hover,
.customize-support button:focus,
.customize-support input[type=”button”]:hover,
.customize-support input[type=”button”]:focus,
.customize-support input[type=”reset”]:hover,
.customize-support input[type=”reset”]:focus,
.customize-support input[type=”submit”]:hover,
.customize-support input[type=”submit”]:focus,
.customize-support .page-links a:hover,
.customize-support .page-links a:focus,
.customize-support .pagination .nav-links .prev:hover,
.customize-support .pagination .nav-links .prev:focus,
.customize-support .pagination .nav-links .next:hover,
.customize-support .pagination .nav-links .next:focus,
.customize-support button[disabled]:hover,
.customize-support input[type=”button”][disabled]:hover,
.customize-support input[type=”reset”][disabled]:hover,
.customize-support input[type=”submit”][disabled]:hover,
.customize-support .menu-toggle.toggled-on:hover,
.customize-support .widget_calendar tbody a:hover,
.customize-support .widget_calendar tbody a:focus,
.customize-support .page-links a:hover,
.customize-support .page-links a:focus
{
background: #2a3691; color:#efddc9;
}
That fixes the main buttons, at least for me. It’s probably more code than is necessary, but it works.