/* =====================================================
   Search Bar (美術館アーカイブ統合スタイル)
   深津市立近代美術館の品格と静謐さに合わせた上部検索バー
   ===================================================== */

.top-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.25rem;
  padding: 0.6rem 1.75rem;
  background: rgba(18, 24, 32, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(184, 145, 80, 0.25);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
  position: sticky;
  top: 0;
  z-index: 50;
  transition: all 0.3s ease;
}

/* 左側のアーカイブ識別ラベル */
.top-nav::before {
  content: "FUKATSU MODERN ART MUSEUM // DIGITAL ARCHIVE SYSTEM";
  font-family: 'Cinzel', var(--font-serif), serif;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: rgba(212, 171, 106, 0.85);
  font-weight: 500;
  white-space: nowrap;
}

.top-nav__title {
  font-family: var(--font-serif);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: #e2e8f0;
  margin: 0;
}

.top-nav__search {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: auto;
}

.top-nav__search input {
  min-width: 260px;
  max-width: 45vw;
  height: 34px;
  padding: 0 0.9rem;
  font-family: var(--font-sans);
  font-size: 0.82rem;
  color: #f1f5f9;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 4px;
  outline: none;
  letter-spacing: 0.04em;
  transition: all 0.25s ease;
}

.top-nav__search input::placeholder {
  color: rgba(148, 163, 184, 0.7);
  font-size: 0.8rem;
}

.top-nav__search input:focus {
  background: rgba(255, 255, 255, 0.12);
  border-color: #b89150;
  box-shadow: 0 0 0 2px rgba(184, 145, 80, 0.25);
}

.top-nav__search button {
  height: 34px;
  padding: 0 1rem;
  font-family: var(--font-serif);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: #fdfcf9;
  background: linear-gradient(135deg, #2b3544 0%, #1a222d 100%);
  border: 1px solid rgba(184, 145, 80, 0.45);
  border-radius: 4px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

.top-nav__search button::before {
  content: "🔍";
  font-size: 0.72rem;
  opacity: 0.85;
}

.top-nav__search button:hover {
  background: linear-gradient(135deg, #b89150 0%, #997539 100%);
  border-color: #d4ab6a;
  box-shadow: 0 2px 8px rgba(184, 145, 80, 0.35);
  transform: translateY(-1px);
}

.top-nav__search button:active {
  transform: translateY(0);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
  .top-nav {
    flex-direction: column;
    align-items: stretch;
    padding: 0.5rem 1rem;
    gap: 0.5rem;
  }

  .top-nav::before {
    font-size: 0.65rem;
    text-align: center;
  }

  .top-nav__search {
    width: 100%;
    margin-left: 0;
  }

  .top-nav__search input {
    min-width: 0;
    max-width: none;
    flex: 1;
  }
}