/* ========== Index Page ========== */
.index-content {
  padding: 0 32px 60px;
}

.hero {
  text-align: center;
  padding: 48px 20px 36px;
  background: linear-gradient(180deg, #faf8f4 0%, transparent 100%);
}

.hero-title {
  font-size: 2.8rem;
  font-weight: 700;
  letter-spacing: 16px;
  color: #1a1a1a;
  margin-bottom: 8px;
  text-indent: 16px;
}

.hero-sub {
  font-size: 15px;
  color: #8b7e6a;
  letter-spacing: 2px;
  font-family: "Noto Sans SC", sans-serif;
}

.hero-search {
  margin-top: 24px;
  max-width: 420px;
  margin-left: auto;
  margin-right: auto;
}

.hero-search input {
  width: 100%;
  padding: 12px 20px;
  border: 2px solid var(--border);
  border-radius: 12px;
  font-size: 15px;
  outline: none;
  background: #fff;
  font-family: "Noto Sans SC", sans-serif;
  transition: all var(--transition);
  box-shadow: var(--shadow);
}

.hero-search input:focus {
  border-color: #c0392b;
  box-shadow: 0 0 0 4px rgba(192,57,43,0.08), var(--shadow-lg);
}

.cat-tabs {
  display: flex;
  gap: 8px;
  padding: 0 20px 20px;
  justify-content: center;
  flex-wrap: wrap;
}

.cat-tab {
  padding: 8px 18px;
  border: 1.5px solid var(--border);
  border-radius: 20px;
  background: #fff;
  font-size: 13.5px;
  cursor: pointer;
  transition: all var(--transition);
  font-family: "Noto Sans SC", sans-serif;
  color: var(--text-secondary);
}

.cat-tab:hover {
  border-color: #aaa;
  color: var(--text);
}

.cat-tab.active {
  background: #1a1a2e;
  color: #fff;
  border-color: #1a1a2e;
}

.cat-section {
  margin-bottom: 40px;
}

.cat-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
  padding: 0 4px;
}

.cat-icon {
  width: 40px; height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  color: #fff;
  flex-shrink: 0;
}

.cat-info h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #1a1a1a;
  letter-spacing: 2px;
}

.cat-desc {
  font-size: 12.5px;
  color: #8b7e6a;
  font-family: "Noto Sans SC", sans-serif;
}

.cat-badge {
  margin-left: auto;
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 500;
  font-family: "Noto Sans SC", sans-serif;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 14px;
}

.book-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  transition: all var(--transition);
  border: 1px solid rgba(0,0,0,0.04);
  display: flex;
  flex-direction: column;
}

.book-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-xl);
  border-color: rgba(0,0,0,0.08);
}

.card-accent {
  height: 3px;
  flex-shrink: 0;
}

.card-body {
  padding: 12px 14px 10px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-title {
  font-size: 14px;
  font-weight: 600;
  color: #1a1a1a;
  margin-bottom: 4px;
  letter-spacing: 1px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.card-preview {
  font-size: 11.5px;
  color: #999;
  line-height: 1.5;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 6px;
}

.card-cat {
  font-size: 10.5px;
  padding: 1px 8px;
  border-radius: 8px;
  font-weight: 500;
  font-family: "Noto Sans SC", sans-serif;
}

.card-size {
  font-size: 10.5px;
  color: #bbb;
  font-family: "Noto Sans SC", sans-serif;
}

.book-card.hidden { display: none; }
.cat-section.hidden { display: none; }

@media (max-width: 1200px) {
  .cards-grid { grid-template-columns: repeat(4, 1fr); }
}
@media (max-width: 900px) {
  .cards-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 640px) {
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-title { font-size: 2rem; letter-spacing: 8px; }
  .index-content { padding: 0 12px 40px; }
}