Well, after hours of messing around with the code, it all came down to your solutions
, I forgot to add the position: relative to the original code and then add the position: absolute to the ::before.
It works and I had to do a negative for the left position.
I am guessing that everything will be the same for the other side (right side)
and use ::after also instead of ::before and also change the left: -15px; to right: 15px
I will do the changes for the right side now and see if it works also for the right side.
Thanks for your help!!