/* Wspólny motyw marki. Rysunek TN-S pozostaje niezmieniony. */
.site-shell {
  position: relative;
  isolation: isolate;
  background: radial-gradient(ellipse at 88% 4%, #073853 0, #001e32 39%, #001523 82%);
}
.electrical-backdrop {
  --board-size: clamp(1140px, 110vw, 1660px);
  --board-position: calc(50% + 35px) 0;
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
  mask-image: linear-gradient(#000 0 94%, transparent);
}
.electrical-backdrop::before, .electrical-backdrop::after {
  content: '';
  position: absolute;
  inset: 0;
  background: url('electrical-distribution.svg?v=4') no-repeat var(--board-position) / var(--board-size) auto;
}
.electrical-backdrop::before { opacity: .24; }
.electrical-backdrop::after {
  opacity: 0;
  mask-image: radial-gradient(circle 240px at var(--circuit-x, 75%) var(--circuit-y, 22%), #000, transparent);
  transition: opacity 220ms ease;
}
.electrical-backdrop.is-lit::after { opacity: .4; }
.brand-filter { position: absolute; pointer-events: none; }
.site-shell .logo-crop img { filter: url(#logo-ink); }

@media (max-width: 900px) {
  .electrical-backdrop { --board-position: center 460px; --board-size: 1250px; opacity: .65; mask-image: linear-gradient(transparent 12%, #000 45%, transparent 98%); }
}
@media (prefers-reduced-motion: reduce) {
  .electrical-backdrop::after { transition: none; }
}