Problems styling the calendar

Hi. Im trying to style better the calendar view of my events because sometimes it overlapps with others and does not seem good. I need some help changing the style so I can accomplish something like the second photo Im attaching it.

First Photo (how it looks in my actual website): https://imgur.com/PQZDLbo

Second photo (how i want it to look): https://imgur.com/ApXp4BC

I hope you can help me how can I accomplish something like that.

Thanks