Centering in the widget

Is there a way to center the calendar inside the widget? I just added a new theme, “Artificer” by woothemes, and the calendar looks weird in the sidebar. Do I need to make the sidebar wider, or can the calendar be centered?

My site is here:
http://www.thebrasswardrobe.com/

https://ww.wp.xz.cn/plugins/google-calendar-widget/