problem event post

I bought All In One Event (with Frontend Submissions) for another website, it works perfectly, but not for this website that does not correctly display the event in post (instance) mode (however different calendar views are working fine):
https://lecim.com/event/concert-des-eleves/?instance_id=5

Is it possible to overwrite CSS code of theme?
Any idea?

Hi Gilles,

Please try the following css code, event details should appear:

.single-ai1ec_event .ai1ec-event-details
{
	margin-top: 200px;
}

Thank for your help.

It’s better but still no post thumbnail image!
https://lecim.com/event/jam-du-mois/?instance_id=4

do you think I have to try with other values?