Removing white space between image block and footer

Site URL: https://www.playcollaborativearts.com/

Hi friends!  I am looking to remove the random strip of white between the content and the footer, and if I'm unable to do this I would like that white to be coded to black to match the header 🙂. Thank you so much for your help! 

**I have tried all of the S M L block, positions, sizes etc

ps. on smaller screens it is not there....

I tested some screen sizes & it looks fine. Which screen size do you see problem?