Good evening Nicolas and welcome back!
Thank you for reaching out to us.
I would love to help you with this topic.
The key is to use the good old @media CSS rules
I would personally recommend simply setting a different rule for mobiles
Try adding the following CSS rule to your style.css file or in your Custom CSS metabox:
@media only screen and (max-device-width : 736px) { .tribe-events-single {
max-width: 90% !important;
}
}
If, for some reason, it does not kick-in, simply add another class or ID in the path to the container (making the CSS rule more specific).
Let me know how that goes.
Best regards,
Geoff B.