But when i sync only the colors of the calender sync right? The colors of the events are getting messi

Yes, and that’s exactly my problem. I want different event colors inside one shared calendar, depending on the person – not different calendars per person. With CalDAV only the calendar color syncs, not the event colors, so everything ends up in the same color on iOS or in other apps. That makes it unusable as a TimeTree replacement for shared family or friend planning. CalDAV just isn’t designed for per-event color syncing across platforms.