Styling of Events+ Calendar Buttons

Hi,
We have an issue with the way the events+ calendar is styling buttons. When someone is not logged into the site through the wordpress login, the styling of the acceptance (yes, no, maybe) buttons disappears. I will add a screenshot. The url that we have the calendar placed on is: http://felegehiywot.iconicdigitalmedia.com/youth-outreach-events
Thanks!