.flatpickr-day.month.selected {
  border-radius: 0;
  box-shadow: -5px 0 0 #569ff7, 5px 0 0 #569ff7
}
.flatpickr-day.month.selected.startRange {
  border-radius: 50px 0 0 50px;
}
.flatpickr-day.month.selected.endRange {
  border-radius: 0 50px 50px 0;
}