[SASS, CSS] i wish to replace from Stars to my imgs url, but how?

hi

i look beautiful code: https://codepen.io/sarazond/pen/LYGbwj
i did tried many times but not successful…
i did try read the guide of SASS,CSS but nothing find solution…
my head is fire,stress…mission is failed …sigh…

so i’m register here to ask you to help me find solution…
i wish to replace all stars to my images randoms:

…/bg-003.png
…/bg-004.png

do you can resolve it for me?

thank you