Hi Murilo,
Thanks for getting in touch and for checking out our plugins — I hope The Events Calendar and Events Calendar PRO are both a good fit for your site. 🙂
Yes, it is possible to edit the colors on the calendar. You can do that with CSS or, if you have Events Calendar PRO installed, then you can change the color settings in the WordPress Customizer, under Appearance > Settings.
Our Themer’s Guide is a great place to see all the ways in which the calendar can be customized:
https://theeventscalendar.com/knowledgebase/themers-guide/
And, lastly, there is a plugin that we didn’t create but that works very well with The Events Calendar to color code events by category:
The Events Calendar: Category Colors
Does this help answer your question? Please let me know. 🙂
Cheers!
Geoff