I think you are missing (or maybe I just couldn’t find them) two , one to close your row and another to close your section.
Much helpful
Thanks Hilary
Nice job Siya !!! … but one thing can u place image in such a way that either background color silver is not visible from both the end or leave a little space from both side of image as I can see from one end their is space and from other their is none . I feel this will make it better 
Also please provide feedback for mine https://codepen.io/hsrocks7/full/mwyVya