Sidebar for events showing the wrong width

Hi,

If I understand correctly, BeTheme should be compatible with Events Calendar. On our development website (see events overview page @ http://u26268p20302.web0078.zxcs.nl/agenda/), for sidebars in theme options, I set the width of the sidebar to 30%. However on the events page the sidebar is showing in a <div class="four columns"> which results in a sidebar of only 23%.

How can I fix this?

Thanks & regards,
Monique