How do I add custom styling to the FunnelFLARE appointment scheduler calendar?

Browse to the page editor for the appointment page that you want to adjust. Hover over the form element so that the menu item appears. Click the pencil

This will open the form editor. Click the styles button on the sidebar:

Most of the styles can be edited using the style editor. If you want to use CSS, click the CSS block to expose the CSS editor

The CSS block can be edited directly

Paste this code:

%FORM.HTML_ID% .appointment-calendar-wrapper .disabled-date {
   /* disabled days - no available appts */
/* example  color: #9f9f9f !important; */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table tbody tr td:first-of-type {
   /* Sundays */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table tbody tr td:last-of-type {
   /* sundays */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table thead tr:last-of-type {
   /* weekday names row */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table thead tr:last-of-type td {
   /* weekday names cell */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table thead tr:nth-of-type(2) {
   /* month name row */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table thead tr:nth-of-type(2) .prev {
   /* previous month button */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table thead tr:nth-of-type(2) .next {
   /* next month button */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .datepicker-days table thead tr:nth-of-type(2) .datepicker-switch {
   /* month name */
}

%FORM.HTML_ID% .appointment-calendar-wrapper .appointment-calendar {
   /* calendar table */
  width: 100%;
  height: 600px;
}

%FORM.HTML_ID% .appointment-calendar-wrapper .appointment-timeslots {
   /* timeslot section */
  width: 100%;
}

%FORM.HTML_ID% .appointment-calendar-wrapper .appointment-timeslots .time-slot {
   /* single timeslot*/

}

%FORM.HTML_ID% .appointment-calendar-wrapper .appointment-timeslots .time-slot.active-slot {
   /* single timeslot*/
}

%FORM.HTML_ID% .appointment-calendar-wrapper {
   /* calendar wrapper */
}

%FORM.HTML_ID% .appointments .appointment-length{
   /* appointment length */
}

add custom CSS to adjust the styles of the object in the object's section.