Calendar colors all turned one shade of green

Calendar colors all turned one shade of green

Hello,

I have about 7 calendars set-up in my Zoho Calendar, all of them had been set to different colors. I logged-in yesterday morning and found that all calendars are now a single shade of green. I would not mind changing the colors back, but it doesn't seem like I can edit the colors. When I click on the calendar in the list, it simply shows or hides the associated activities. How can I change the colors for the calendars?

Thanks in advance.