:root {
  --bg: #f7f3eb;
  --card: #fffdf8;
  --text: #1e1a16;
  --muted: #6b6358;
  --accent: #2d5a3d;
  --accent-light: #e8f0ea;
  --border: #e0d6c8;
  --shadow: 0 2px 12px rgba(30, 26, 22, 0.08);
  --font-ing: Georgia, "Times New Roman", serif;
  --font-ui: system-ui, -apple-system, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  line-height: 1.5;
}

a {
  color: var(--accent);
  text-decoration: none;
}

.app-header {
  background: linear-gradient(135deg, #2d5a3d 0%, #1e3d2a 100%);
  color: #fff;
  padding: 1.25rem 1rem 1.5rem;
  text-align: center;
}

.app-header h1 {
  margin: 0;
  font-family: var(--font-ing);
  font-size: 1.6rem;
  font-weight: normal;
  letter-spacing: 0.04em;
}

.app-header p {
  margin: 0.35rem 0 0;
  opacity: 0.88;
  font-size: 0.92rem;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 1rem;
}

.categories {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 0.75rem;
  margin: 1rem 0 1.5rem;
}

.cat-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
  padding: 1rem 0.5rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--card);
  cursor: pointer;
  font: inherit;
  color: var(--text);
  box-shadow: var(--shadow);
  transition: transform 0.15s, border-color 0.15s;
}

.cat-btn:hover,
.cat-btn.active {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.cat-btn .icon {
  font-size: 1.6rem;
}

.cat-btn .label {
  font-size: 0.88rem;
  font-weight: 600;
}

.section-title {
  font-size: 1rem;
  color: var(--muted);
  margin: 0 0 0.75rem;
  font-weight: 600;
}

.book-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.book-card {
  display: flex;
  gap: 1rem;
  padding: 1rem;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: border-color 0.15s;
}

.book-card:hover {
  border-color: var(--accent);
}

.book-cover {
  width: 56px;
  height: 72px;
  border-radius: 6px;
  background: var(--accent-light);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-family: var(--font-ing);
  font-size: 0.7rem;
  text-align: center;
  color: var(--accent);
  padding: 4px;
  line-height: 1.2;
}

.book-info h3 {
  margin: 0 0 0.25rem;
  font-family: var(--font-ing);
  font-size: 1.1rem;
  font-weight: normal;
}

.book-info .meta {
  font-size: 0.82rem;
  color: var(--muted);
  margin-bottom: 0.35rem;
}

.book-info .desc {
  font-size: 0.88rem;
  color: var(--text);
}

.empty {
  text-align: center;
  color: var(--muted);
  padding: 2rem 1rem;
}

.install-hint {
  margin: 1.5rem 0;
  padding: 0.85rem 1rem;
  background: var(--accent-light);
  border-radius: 10px;
  font-size: 0.88rem;
  color: var(--accent);
  text-align: center;
}

.admin-link {
  text-align: center;
  margin: 1rem 0 2rem;
  font-size: 0.85rem;
}

.admin-link a {
  color: var(--muted);
}

/* Reader */
.reader-app {
  min-height: 100vh;
  padding-top: var(--reader-top-h, 6.5rem);
  padding-bottom: 4.5rem;
}

.reader-top {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--card);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 8px rgba(30, 26, 22, 0.06);
}

.reader-header {
  padding: 0.65rem 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  border-bottom: 1px solid var(--border);
}

.reader-header .back {
  border: none;
  background: none;
  font-size: 1.3rem;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  color: var(--accent);
}

.reader-header .title {
  flex: 1;
  font-family: var(--font-ing);
  font-size: 1rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.reader-toolbar {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
  padding: 0.5rem 0.75rem;
  background: var(--card);
}

.reader-toolbar button,
.reader-toolbar a.btn {
  padding: 0.4rem 0.7rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  font-size: 0.82rem;
  cursor: pointer;
  color: var(--text);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

.reader-toolbar button:hover,
.reader-toolbar a.btn:hover {
  border-color: var(--accent);
}

.reader-page {
  max-width: 42rem;
  margin: 0 auto;
  padding: 1.25rem 1.25rem 5rem;
}

.page-label {
  text-align: center;
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 1rem;
}

.page-body {
  font-family: var(--font-ing);
  font-size: 1.05rem;
  line-height: 1.65;
  text-align: justify;
}

.page-body p {
  margin: 0 0 0.85rem;
}

.page-figure {
  margin: 0 0 1rem;
  text-align: center;
}

.page-figure img {
  max-width: 100%;
  height: auto;
  border-radius: 6px;
  box-shadow: var(--shadow);
}

.reader-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  padding: 0.75rem 1rem;
  background: var(--card);
  border-top: 1px solid var(--border);
  box-shadow: 0 -2px 12px rgba(0, 0, 0, 0.06);
}

.reader-nav button {
  padding: 0.55rem 1.1rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-size: 0.9rem;
  cursor: pointer;
}

.reader-nav button:disabled {
  opacity: 0.4;
  cursor: default;
}

.reader-nav .page-num {
  align-self: center;
  font-size: 0.88rem;
  color: var(--muted);
}

@media (min-width: 768px) {
  .app-header h1 {
    font-size: 2rem;
  }
  .reader-app {
    padding-bottom: 1.5rem;
  }
  .reader-page {
    padding-bottom: 1rem;
  }
  .reader-nav {
    position: static;
    max-width: 42rem;
    margin: 0 auto 2rem;
    border: 1px solid var(--border);
    border-radius: 12px;
    box-shadow: var(--shadow);
  }
}

/* Admin */
.admin-container {
  max-width: 640px;
}

.admin-panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.25rem;
  margin-bottom: 1.25rem;
  box-shadow: var(--shadow);
}

.admin-panel h2 {
  margin: 0 0 1rem;
  font-size: 1.1rem;
  color: var(--accent);
}

.admin-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

.admin-form label {
  display: block;
  margin-bottom: 0.75rem;
  font-size: 0.88rem;
  font-weight: 600;
}

.admin-form input,
.admin-form select,
.admin-form textarea {
  display: block;
  width: 100%;
  margin-top: 0.3rem;
  padding: 0.5rem 0.65rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  font: inherit;
  background: #fff;
}

.admin-grid {
  display: grid;
  gap: 0.75rem;
}

@media (min-width: 560px) {
  .admin-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.admin-files {
  border: 1px dashed var(--border);
  border-radius: 10px;
  padding: 0.75rem 1rem;
  margin: 1rem 0;
}

.admin-files legend {
  padding: 0 0.35rem;
  font-size: 0.85rem;
  color: var(--muted);
}

.admin-btn {
  padding: 0.55rem 1.1rem;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font: inherit;
  cursor: pointer;
}

.admin-btn.secondary {
  background: var(--card);
  color: var(--text);
  border: 1px solid var(--border);
}

.admin-btn.danger {
  background: #8b3a3a;
  padding: 0.35rem 0.7rem;
  font-size: 0.82rem;
}

.admin-msg {
  margin-top: 0.75rem;
  font-size: 0.88rem;
}

.admin-msg.ok {
  color: var(--accent);
}

.admin-msg.err {
  color: #8b3a3a;
}

.admin-book-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.admin-book-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--border);
}

.admin-book-item .meta {
  display: block;
  font-size: 0.78rem;
  color: var(--muted);
  font-weight: normal;
}