Boxed layout width

When I choose a boxed width of 1140, it actually sets the width to 1240.

I was able to overcome this by adding the following custom css:

#main-wrapper.hb-boxed-layout, .container { width: 1140px !important; }
.hb-boxed-layout #header-inner.stuck #header-inner-bg { width: 1140px !important; }
.hb-boxed-layout #sticky-shop-button { left: 1080px !important }

It’s fine, and it worked. However, I’m wondering why the setting in the Highend options adds an additional 100px to the width.

Thanks,
Chris