Template:PosterGalleryCSS.css

/* Template:PosterGalleryCSS.css */
.ksi-posters .gallerybox .thumb {
  border: 1px solid #777;
  background: #111;         /* dark card behind the image */
  padding: 6px;             /* space between border and image */
  box-shadow: 0 1px 4px rgba(0,0,0,.4);
}
.ksi-posters .thumb img { display: block; width: 100%; height: auto; }
.ksi-posters .gallerytext {
  color: #fff;          /* make non-link caption text white */
  font-size: 90%;
  padding-top: 4px;
  text-align: center;
}
/* Force white caption text in packed galleries */
ul.gallery.mw-gallery-packed.ksi-posters li.gallerybox .gallerytext {
  color: #fff !important;
}

/* Keep links using the site’s normal link color */
ul.gallery.mw-gallery-packed.ksi-posters li.gallerybox .gallerytext a,
ul.gallery.mw-gallery-packed.ksi-posters li.gallerybox .gallerytext a:visited {
  color: revert !important;  /* fall back to skin/site link color */
}