Hello,

I cannot find the ACP or CSS parameter to change the color of the "active day" [ 1 ] and the color of the duration period for an event

Thank you for your support

 

For the background color of the current day:

.cCalendar td.cCalendar_today, .cCalendarWeek div.cCalendar_today {
background: #FF0000;
}

The title of the event over the entire period is set as part of the calendar the event is assigned to. You change it in the ACP in the calendar settings. 

Merci !