/* ==========================================================================
   ตำรา ๑๐๐ ปี eBooks — Stylesheet
   Design language: "หนังสือเก่าที่ยังมีชีวิต" — a warm, paper-and-book-cloth
   pink palette with gold foil-stamp accents, referencing the physical
   textures of a 100-year archive while staying crisp and modern on screen.
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. Design tokens
   -------------------------------------------------------------------------- */
:root {
  /* Color: heritage cream + gold + dark brown */
  --color-bg:            #FAF8F2;   /* warm cream background */
  --color-surface:       #F2F2F2;   /* card surface */
  --color-surface-soft:  #FAF8F2;   /* subtle alt surface */
  --color-primary:       #D4AF37;   /* dark brown — primary */
  --color-primary-dark:  #3A2B26;   /* darker brown — hover/pressed */
  --color-primary-tint:  #d1ac3c;   /* light beige chip/badge fill */
  --color-primary-tint-2:#F3EFE1;   /* even lighter wash */
  --color-gold:          #D9B13B;   /* gold accent */
  --color-gold-dark:     #2e333d;
  --color-ink:           #3A2B26;   /* near-black warm text */
  --color-ink-soft:      #6E5B4E;   /* secondary text */
  --color-ink-faint:     #534b37;   /* tertiary text / placeholders */
  --color-line:          #F3EFE1;   /* hairline borders */
  --color-line-soft:     #ECE8D8;

  /* Type */
  --font-display: 'Kanit', sans-serif;
  --font-body: 'Kanit', sans-serif;

  /* Shape & motion */
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-pill: 999px;
  --shadow-card: 0 2px 8px rgba(58, 43, 38, 0.06), 0 1px 2px rgba(58, 43, 38, 0.04);
  --shadow-card-hover: 0 18px 30px -12px rgba(89, 60, 54, 0.28), 0 4px 10px rgba(58, 43, 38, 0.06);
  --shadow-modal: 0 30px 60px -15px rgba(58, 43, 38, 0.35);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 0.18s;
  --dur-med: 0.32s;
}

@font-face {
  font-family: 'Kanit';
  src: url('kanit/Kanit-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
}
@font-face {
  font-family: 'Kanit';
  src: url('kanit/Kanit-Bold.ttf') format('truetype');
  font-weight: 700;
  font-style: normal;
}
@font-face {
  font-family: 'Kanit';
  src: url('kanit/Kanit-Italic.ttf') format('truetype');
  font-weight: 400;
  font-style: italic;
}
@font-face {
  font-family: 'Kanit';
  src: url('kanit/Kanit-BoldItalic.ttf') format('truetype');
  font-weight: 700;
  font-style: italic;
}

/* --------------------------------------------------------------------------
    2. Reset & base
    -------------------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

h1, h2, h3 { font-family: var(--font-display); margin: 0; color: var(--color-ink); }
p { margin: 0; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; }
ul, dl, dd { margin: 0; padding: 0; }

img { max-width: 100%; display: block; }

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: 4px;
}

.btn-icon svg, svg { fill: none; }

/* --------------------------------------------------------------------------
   3. Header
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-line);
}

.header-inner {
  max-width: 1180px;
  padding: 14px 24px;
  margin: 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
}

.brand-seal-img { width: 32px; height: 32px; flex-shrink: 0; }
.seal-svg { width: 100%; height: 100%; }
.seal-ring { fill: none; stroke: var(--color-primary); stroke-width: 3; stroke-dasharray: 4 4; }
.seal-ring-inner { fill: var(--color-primary-tint); stroke: var(--color-gold); stroke-width: 1.5; }
.seal-number { font-family: var(--font-display); font-weight: 600; font-size: 20px; fill: var(--color-primary-dark); }
.seal-label { font-family: var(--font-body); font-size: 11px; fill: var(--color-gold-dark); }

.brand-text { display: flex; flex-direction: column; line-height: 1.25; }
.brand-title { font-family: var(--font-display); font-weight: 600; font-size: 19px; color: var(--color-primary-dark); }
.brand-subtitle { font-size: 12.5px; color: var(--color-ink-soft); }

/* --------------------------------------------------------------------------
   4. Hero
   -------------------------------------------------------------------------- */
.hero {
  padding: 56px 24px 36px;
  text-align: center;
  background:
    radial-gradient(ellipse at 20% 0%, var(--color-primary-tint-2) 0%, transparent 55%),
    radial-gradient(ellipse at 85% 10%, #EDE4C0 0%, transparent 50%);
  animation: fadeUp var(--dur-med) var(--ease-out) both;
}

.hero-inner { max-width: 680px; margin: 0 auto; }

.hero-eyebrow {
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--color-gold-dark);
  font-weight: 600;
  margin-bottom: 12px;
}

.hero-heading {
  font-size: clamp(28px, 4.5vw, 40px);
  font-weight: 600;
  line-height: 1.35;
  color: var(--color-ink);
}

.hero-copy {
  margin-top: 16px;
  color: var(--color-ink-soft);
  font-size: 16px;
  max-width: 560px;
  margin-left: auto;
  margin-right: auto;
}

/* --------------------------------------------------------------------------
   5. Search & filter
   -------------------------------------------------------------------------- */
.search-section { padding: 0 24px 8px; }
.search-section-inner { max-width: 900px; margin: 0 auto; }

.search-bar {
  position: relative;
  display: flex;
  align-items: center;
  background: var(--color-surface);
  border: 1.5px solid var(--color-line);
  border-radius: var(--radius-pill);
  padding: 4px 8px;
  box-shadow: var(--shadow-card);
  transition: border-color var(--dur-fast) var(--ease-out), box-shadow var(--dur-fast) var(--ease-out);
}

.search-bar:focus-within {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-tint-2);
}

.search-icon {
  width: 20px; height: 20px;
  margin-left: 12px;
  flex-shrink: 0;
  stroke: var(--color-ink-faint);
  stroke-width: 2;
  stroke-linecap: round;
}

.search-input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  padding: 13px 10px;
  font-family: var(--font-body);
  font-size: 15.5px;
  color: var(--color-ink);
}
.search-input::placeholder { color: var(--color-ink-faint); }

.clear-search {
  border: none;
  background: var(--color-primary-tint);
  color: var(--color-primary-dark);
  width: 28px; height: 28px;
  border-radius: 50%;
  font-size: 18px;
  line-height: 1;
  margin-right: 6px;
  flex-shrink: 0;
  transition: background var(--dur-fast) var(--ease-out);
}
.clear-search:hover { background: var(--color-primary); color: #fff; }

.filter-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 18px 2px 6px;
}

.filter-pill {
  flex-shrink: 0;
  border: 1.5px solid var(--color-line);
  background: #E8E4C9;
  color: #90776D;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 500;
  white-space: nowrap;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: transform, background-color, border-color, color;
  backface-visibility: hidden;
}

.filter-pill:hover {
  border-color: var(--color-primary);
  color: var(--color-primary-dark);
}

.filter-pill.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
  box-shadow: 0 4px 10px -2px rgba(161, 61, 92, 0.4);
}

/* --------------------------------------------------------------------------
   6. Results meta
   -------------------------------------------------------------------------- */
.results-meta-wrap { max-width: 1180px; margin: 0 auto; padding: 18px 24px 0; }
.results-meta { font-size: 13.5px; color: var(--color-ink-faint); }
.results-meta strong { color: var(--color-primary-dark); font-weight: 600; }

/* --------------------------------------------------------------------------
   7. Book grid & cards
   -------------------------------------------------------------------------- */
.library-section { max-width: 1180px; margin: 0 auto; padding: 16px 24px 80px; }

.book-grid {
  view-transition-name: book-grid;
  min-height: 60vh;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
  gap: 26px 22px;
  transition: opacity 0.35s ease 0.05s, transform 0.35s ease 0.05s;
}

.book-grid.is-fading {
  opacity: 0;
  transform: translateY(6px);
  transition: opacity 0.25s ease, transform 0.25s ease;
}

::view-transition-group(book-grid) {
  animation-duration: 0.35s;
}
::view-transition-old(book-grid) {
  animation-name: fade-out;
}
::view-transition-new(book-grid) {
  animation-name: fade-in;
  animation-delay: 0.05s;
}

.book-card {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  cursor: pointer;
  border: 1px solid var(--color-line-soft);
  transition: transform 0.45s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.45s cubic-bezier(0.16, 1, 0.3, 1);
  animation: fadeUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
  display: flex;
  flex-direction: column;
  will-change: transform, box-shadow;
  backface-visibility: hidden;
}

.book-card:hover,
.book-card:focus-visible {
  transform: translateY(-8px);
  box-shadow: var(--shadow-card-hover);
}

.book-card:hover .book-cover-img { transform: scale(1.05); }
.book-card:hover .cover-stamp { transform: rotate(-10deg) scale(1.08); }

/* -- Cover: generated placeholder (real photo can replace via .image field) -- */
.book-cover {
  position: relative;
  aspect-ratio: 3 / 4;
  overflow: hidden;
  background: var(--color-primary);
}

.book-cover-img {
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: 0;
  transition: opacity 0.35s ease, transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: transform, opacity;
  backface-visibility: hidden;
}
.book-cover-img.loaded {
  opacity: 1;
}

.book-cover-generated {
  width: 100%; height: 100%;
  display: flex;
  align-items: flex-end;
  padding: 16px;
  transition: transform var(--dur-med) var(--ease-out);
  position: relative;
}

.cover-glyph {
  font-family: var(--font-display);
  font-weight: 600;
  color: rgba(255,255,255,0.92);
  font-size: 15px;
  line-height: 1.35;
  text-shadow: 0 1px 3px rgba(0,0,0,0.15);
}

/* Foil-stamp year seal, echoing an archive due-date stamp */
.cover-stamp {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--color-gold);
  border: 1.5px dashed var(--color-gold);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  transform: rotate(6deg);
  transition: transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 0 3px 8px rgba(0,0,0,0.18);
  will-change: transform;
  backface-visibility: hidden;
}
.cover-stamp-year { font-family: var(--font-display); font-weight: 700; font-size: 12.5px; color: #fff; line-height: 1; }
.cover-stamp-label { font-size: 7.5px; color: #fff; margin-top: 1px; letter-spacing: 0.02em; }

/* Category texture variants — brown/gold/cream family, different pattern per category */
.cover-cat-0 { background: linear-gradient(155deg, #7A4A3D, #593C36); background-image: linear-gradient(155deg, #7A4A3D, #593C36), repeating-linear-gradient(45deg, rgba(255,255,255,0.07) 0 2px, transparent 2px 14px); }
.cover-cat-1 { background: linear-gradient(155deg, #B8943B, #8A6D2B); background-image: linear-gradient(155deg, #B8943B, #8A6D2B), radial-gradient(circle, rgba(255,255,255,0.16) 1.5px, transparent 1.6px); background-size: auto, 16px 16px; }
.cover-cat-2 { background: linear-gradient(155deg, #6E4A3D, #4E3028); background-image: linear-gradient(155deg, #6E4A3D, #4E3028), repeating-linear-gradient(90deg, rgba(255,255,255,0.08) 0 1px, transparent 1px 12px); }
.cover-cat-3 { background: linear-gradient(155deg, #5A4A3D, #3E3028); background-image: linear-gradient(155deg, #5A4A3D, #3E3028), repeating-linear-gradient(-45deg, rgba(255,255,255,0.06) 0 2px, transparent 2px 16px); }
.cover-cat-4 { background: linear-gradient(155deg, #8A7A3D, #6A5A2B); background-image: linear-gradient(155deg, #8A7A3D, #6A5A2B), repeating-linear-gradient(0deg, rgba(255,255,255,0.09) 0 1px, transparent 1px 10px); }
.cover-cat-5 { background: linear-gradient(155deg, #7A5A4A, #5A3A2E); background-image: linear-gradient(155deg, #7A5A4A, #5A3A2E), repeating-linear-gradient(60deg, rgba(255,255,255,0.07) 0 2px, transparent 2px 13px); }
.cover-cat-6 { background: linear-gradient(155deg, #6A5A3D, #4A3A28); background-image: linear-gradient(155deg, #6A5A3D, #4A3A28), radial-gradient(circle, rgba(255,255,255,0.14) 2px, transparent 2.1px); background-size: auto, 20px 20px; }
.cover-cat-7 { background: linear-gradient(155deg, #5A4A3D, #3E2E28); background-image: linear-gradient(155deg, #5A4A3D, #3E2E28), repeating-linear-gradient(135deg, rgba(255,255,255,0.07) 0 2px, transparent 2px 15px); }
.cover-cat-8 { background: linear-gradient(155deg, #5A6A54, #3E4E38); background-image: linear-gradient(155deg, #5A6A54, #3E4E38), repeating-linear-gradient(90deg, rgba(255,255,255,0.08) 0 1px, transparent 1px 11px); }
.cover-cat-9 { background: linear-gradient(155deg, #5A6A7A, #3E4E58); background-image: linear-gradient(155deg, #5A6A7A, #3E4E58), repeating-linear-gradient(45deg, rgba(255,255,255,0.07) 0 2px, transparent 2px 14px); }

.book-info { padding: 14px 16px 18px; display: flex; flex-direction: column; gap: 6px; flex: 1; background: #FFFFFF; }

.book-category-tag {
  align-self: flex-start;
  font-size: 11.5px;
  font-weight: 600;
  color: #8D6E63;
  background: #E8E4C9;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
}

.book-title {
  font-family: var(--font-display);
  font-size: 15.5px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--color-ink);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  cursor: default;
}

.book-author { font-size: 13px; color: var(--color-ink-soft); margin-top: auto; padding-top: 4px; }

/* --------------------------------------------------------------------------
    7.5 Pagination
    -------------------------------------------------------------------------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 32px 24px 60px;
}
.pagination-btn {
  border: 1.5px solid var(--color-line);
  background: var(--color-surface);
  color: var(--color-ink-soft);
  padding: 10px 20px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 500;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: transform, opacity;
  backface-visibility: hidden;
}
.pagination-btn:hover:not(:disabled) {
  border-color: var(--color-primary);
  color: var(--color-primary-dark);
  transform: translateY(-1px);
}
.pagination-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}
.page-info {
  font-size: 14px;
  color: var(--color-ink-soft);
  font-weight: 500;
  min-width: 100px;
  text-align: center;
}

/* --------------------------------------------------------------------------
    8. Empty state
    -------------------------------------------------------------------------- */
.empty-state { text-align: center; padding: 70px 20px; }
.empty-icon { width: 56px; height: 56px; margin: 0 auto 18px; stroke: var(--color-primary); stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.empty-title { font-family: var(--font-display); font-size: 18px; font-weight: 600; color: var(--color-ink); }
.empty-copy { font-size: 14px; color: var(--color-ink-soft); margin-top: 6px; }

/* --------------------------------------------------------------------------
   9. Modal
   -------------------------------------------------------------------------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(58, 43, 38, 0.55);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  z-index: 100;
  animation: overlayIn 0.25s cubic-bezier(0.16, 1, 0.3, 1) both;
  will-change: opacity;
  backface-visibility: hidden;
}
.modal-overlay[hidden] { display: none; }

.modal-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  max-width: 860px;
  width: 100%;
  max-height: 88vh;
  overflow-y: auto;
  position: relative;
  box-shadow: var(--shadow-modal);
  animation: modalIn 0.45s cubic-bezier(0.16, 1, 0.3, 1) both;
  will-change: transform, opacity;
  backface-visibility: hidden;
  -webkit-overflow-scrolling: touch;
}

.modal-close {
  position: sticky;
  float: right;
  top: 16px;
  right: 16px;
  margin: 16px 16px -40px 0;
  width: 36px; height: 36px;
  border-radius: 50%;
  border: none;
  background: var(--color-surface-soft);
  color: var(--color-ink-soft);
  font-size: 22px;
  line-height: 1;
  z-index: 5;
  transition: background var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out);
}
.modal-close:hover { background: var(--color-primary); color: #fff; }

.modal-body {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 32px;
  padding: 32px;
}

.modal-cover-col { display: flex; flex-direction: column; gap: 16px; }

.modal-cover {
  aspect-ratio: 3 / 4;
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: 0 10px 24px -8px rgba(58, 43, 38, 0.28);
  display: flex;
  align-items: flex-end;
  padding: 18px;
}
.modal-cover img { width: 100%; height: 100%; object-fit: cover; }

.modal-actions { display: flex; flex-direction: column; gap: 10px; }

.btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  font-size: 14.5px;
  font-weight: 600;
  transition: all var(--dur-fast) var(--ease-out);
  border: 1.5px solid transparent;
}
.btn-icon { width: 17px; height: 17px; stroke: currentColor; stroke-width: 1.8; }

.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:hover { background: var(--color-primary-dark); }

.btn-secondary { background: var(--color-surface); color: var(--color-primary-dark); border-color: var(--color-primary-tint); }
.btn-secondary:hover { background: var(--color-primary-tint-2); border-color: var(--color-primary); }

.modal-info-col { display: flex; flex-direction: column; }

.modal-category-tag {
  align-self: flex-start;
  font-size: 12px;
  font-weight: 600;
  color: var(--color-primary-dark);
  background: #FAF3D1;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  margin-bottom: 12px;
}

.modal-title { font-size: 24px; font-weight: 600; line-height: 1.4; cursor: default; }
.modal-author { font-size: 15px; color: #927E78; margin-top: 6px; }
.modal-author-prefix { color: #927E78; }

.modal-facts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-top: 22px;
  padding: 16px;
  background: var(--color-surface-soft);
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-line-soft);
}
.modal-fact dt { font-size: 11.5px; color: var(--color-ink-faint); margin-bottom: 3px; }
.modal-fact dd { font-size: 14.5px; font-weight: 600; color: #5E4239; margin: 0; }

.modal-section-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-gold-dark);
  letter-spacing: 0.04em;
  margin-bottom: 8px;
}
.modal-description-wrap { margin-top: 26px; }
.modal-description { font-size: 14.5px; color: #6F564E; line-height: 1.85; }
.modal-description p { margin-bottom: 12px; }
.modal-description p:last-child { margin-bottom: 0; }

/* --------------------------------------------------------------------------
   10. Footer
   -------------------------------------------------------------------------- */
.site-footer {
  background: var(--color-primary-tint-2);
  border-top: 1px solid var(--color-line);
  padding: 40px 24px;
  text-align: center;
}
.footer-inner { max-width: 640px; margin: 0 auto; }
.footer-project { font-family: var(--font-display); font-weight: 600; font-size: 16px; color: var(--color-primary-dark); }
.footer-copyright { font-size: 13px; color: var(--color-ink-soft); margin-top: 6px; }
.footer-links { margin-top: 16px; font-size: 13.5px; color: var(--color-ink-soft); }
.footer-links a { transition: color var(--dur-fast) var(--ease-out); }
.footer-links a:hover { color: var(--color-primary-dark); }
.footer-dot { margin: 0 10px; color: var(--color-ink-faint); }

/* --------------------------------------------------------------------------
   11. Animations
   -------------------------------------------------------------------------- */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(18px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fade-out {
  to { opacity: 0; transform: translateY(6px); }
}
@keyframes fade-in {
  from { opacity: 0; transform: translateY(6px); }
}
@keyframes overlayIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}
@keyframes modalIn {
  from { opacity: 0; transform: translateY(24px) scale(0.96); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}

@media (prefers-reduced-motion: reduce) {
  ::view-transition-group(book-grid) { animation-duration: 0.001ms !important; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* --------------------------------------------------------------------------
   12. Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 860px) {
  .modal-body { grid-template-columns: 1fr; }
  .modal-cover-col { flex-direction: row; align-items: flex-start; }
  .modal-cover { width: 150px; flex-shrink: 0; aspect-ratio: 3/4; }
  .modal-actions { flex: 1; justify-content: center; }
}

@media (max-width: 640px) {
  .header-inner { padding: 12px 18px; }
  .brand-title { font-size: 16.5px; }
  .brand-subtitle { font-size: 11.5px; }

  .hero { padding: 40px 18px 28px; }
  .hero-heading br { display: none; }

  .search-section { padding: 0 18px 4px; }
  .library-section { padding: 12px 18px 60px; }
  .results-meta-wrap { padding: 14px 18px 0; }

  .book-grid { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 18px 14px; }
  .book-title { font-size: 14px; }

  .modal-overlay { padding: 0; align-items: flex-end; }
  .modal-card { max-width: 100%; max-height: 92vh; border-radius: var(--radius-lg) var(--radius-lg) 0 0; }
  .modal-body { padding: 24px 20px; gap: 22px; }
  .modal-cover-col { flex-direction: column; }
  .modal-cover { width: 100%; }
  .modal-facts { grid-template-columns: 1fr 1fr; }
  .modal-title { font-size: 20px; }
}

/* --------------------------------------------------------------------------
     13. Loading & Error states
     -------------------------------------------------------------------------- */
.error-state {
  text-align: center;
  padding: 60px 20px;
  max-width: 1180px;
  margin: 0 auto;
}
.error-state p { color: var(--color-primary-dark); font-size: 14.5px; margin-bottom: 12px; }

.skeleton-card {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-line-soft);
  animation: skeletonPulse 1.4s ease-in-out infinite;
}
.skeleton-cover {
  aspect-ratio: 3 / 4;
  background: var(--color-line-soft);
}
.skeleton-body { padding: 14px 16px 18px; display: flex; flex-direction: column; gap: 8px; }
.skeleton-line {
  height: 12px;
  background: var(--color-line-soft);
  border-radius: 6px;
}
.skeleton-line.short { width: 60%; }
@keyframes skeletonPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

/* --------------------------------------------------------------------------
    14. Faculty & Tags
    -------------------------------------------------------------------------- */
.book-faculty {
  font-size: 12.5px;
  color: var(--color-ink-faint);
  margin-top: 2px;
}
.book-tags-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 4px;
}
.book-tag {
  font-size: 11px;
  font-weight: 500;
  color: var(--color-gold-dark);
  background: #FAF3D1;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  border: 1px solid #E8DFA8;
}
.modal-faculty {
  font-size: 13.5px;
  color: var(--color-ink-soft);
  margin-top: 2px;
}
.modal-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}
.modal-tag {
  font-size: 12px;
  font-weight: 500;
  color: var(--color-gold-dark);
  background: #FAF3D1;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  border: 1px solid #E8DFA8;
}