/* ── BACK BUTTON (shared by collection routes) ── */
.back-btn {
  position: fixed;
  top: 24px;
  left: 24px;
  z-index: 1000;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: 'Playfair Display', Georgia, serif;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: #ffffff;
  background: rgba(0, 0, 0, 0.6);
  border: 1px solid #ffffff;
  padding: 12px 22px;
  cursor: pointer;
  overflow: hidden;
  text-decoration: none;
  transition: color 0.4s ease;
  -webkit-backdrop-filter: blur(4px);
  backdrop-filter: blur(4px);
}

.back-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: #ffffff;
  transform: translateX(-100%);
  transition: transform 0.4s ease;
}

.back-btn:hover,
.back-btn:focus-visible {
  color: #000000;
}

.back-btn:hover::before,
.back-btn:focus-visible::before {
  transform: translateX(0);
}

.back-btn:focus-visible {
  outline: 1px solid #ffffff;
  outline-offset: 3px;
}

.back-btn > * {
  position: relative;
  z-index: 1;
}

.back-btn-arrow {
  display: inline-block;
  transition: transform 0.4s ease;
}

.back-btn:hover .back-btn-arrow {
  transform: translateX(-4px);
}

@media (max-width: 600px) {
  .back-btn {
    top: 14px;
    left: 14px;
    padding: 10px 16px;
    font-size: 0.62rem;
    letter-spacing: 0.3em;
  }
}