Unable to resize or reposition blocks

Site URL: https://www.oscarmay.com/new-landing-page

Hi there, 

I've been working on a new page on my website and somehow along the way something has happened and now I can't resize or reposition blocks anywhere on my site. 
I suspected it might be some custom css code I am using on this page - https://www.oscarmay.com/new-landing-page - however I did try removing it and the issue continued so I've added it back in for now. 

I also updated the site logo and changed some fonts using the Styles area, I wouldn't have thought that caused this issue but that's the other thing that has changed. 

Any help would be greatly appreciated!