remove empty space when page content is very short

hi, i have given a background image to the content area of the twenty sixteen theme and removed all paddings etc. to avoid borders.

however, the empty space is visible at the bottom of the content area when the actual content is very short and i am viewing it on large screen monitor (imac 27″ in my case). example: this page.

is there any way (css code) to set the content area height to 100% so the empty space is not visible on large screen monitors?

please help with the CSS…