Scrolling images

Site URL: https://gardenia-tuna-h4hx.squarespace.com

Hi, I added some code to make my gallery a scrolling image gallery as seen below this, but I now have three of them to display my logo's, but I want one(the middle one) to scroll to the right instead of the left, does anyone know how to do this?
The code I used: 

#page {
overflow-x:hidden
}
.gallery-grid-wrapper {
display:flex !important;
animation: slideshow 20s linear infinite
}
.gallery-grid-wrapper .gallery-grid-item {
 min-width: 20%;
 margin-right: 1%
}
@keyframes slideshow {
  0%    { left: 0; }
  100%  { left: -110%; }
}

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