Custom elements/shapes in background CSS

Hello,

I've been trying a few different things to add these little images on the border of my website. I am able to place them on the border, however I can't figure out how to design the code so these images stay on the border no matter the size of the screen it is displayed on. 

I have tried to make one for the regular desktop site and one code specifically for mobile screens that are under 640 px. Although any other size will still affect the positioning of the images.

Any ideas?

I think you will need to use code to adjust it on all screen sizes. If you share link to page where you use elementshapes, we can check easier