You can change the display colors for elements such as the calendar on the booking page from the edit screen for each booking page.

On booking pages with the new design, bookable time slots are shown in gray, and the theme color is used for things such as the date and time the guest has selected. You cannot change the color of the bookable slots themselves to the theme color.

You can change the colors by going to Edit Booking Page > Page > Theme Colors.

You can use a custom color as your theme color by entering a color code or selecting a color from the color picker.
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