Hide Entry details side panel (right side not the left side calendar list panel) in Calendar Day View

Hi

Using MacBook Air and Calendar. I have as separate screen I use for daily planning with Things and Calendar in Split View. I switch between Day / Week view in Calendar. But when in Day view I got an annoying Entry Details View on the right side of the calendar which takes up a huge amount of screen space - effectively a 3 screen split rather than two!

Searched through all settings and menu view tab etc but can't find any way to hide it.

Anyone have a solution please?

Thanks.