I actually quite like it

Its a sorta deconstructed webpage!
However I had a snoop of the code and I can tell you that there is something wrong with your grid layout values in CSS. Im afraid I can't help here since I don't use grid layouts on my sites because I find them too confusing
Traditionally for a site like this, you'd have three divs called: left_bar, main, right_bar - each would be floated and have a set width in CSS - Then in HTML, everything in your left and right bars would go inside their respective divs and that would handle all your layout stuff. It seems like you're trying to use grids to force this kind of old style layout, but I don't think thats what grids were made for, so you're getting this weird vertical stretching that would not happen with floats.
Anyway, Im sure it is fixable and it might be super simple, and maybe a grid knowing-person can respond ^^