:root {
    --bg: #f7f2ea;
    --paper: #fffdf8;
    --ink: #2f2a24;
    --muted: #8a8075;
    --line: #e5ddd2;
    --accent: #8f6f4e;
    --soft: #efe4d6;
    --danger: #a6534b;
  }

  * {
    box-sizing: border-box;
  }

  body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  }

  button,
  input,
  textarea,
  select {
    font: inherit;
  }

  .app-shell {
    width: 100%;
    max-width: 480px;
    min-height: 100vh;
    margin: 0 auto;
    position: relative;
    background: var(--bg);
  }

  #app {
    min-height: 100vh;
    padding: 18px 16px 92px;
  }

  .page-title {
    font-size: 24px;
    font-weight: 700;
    margin: 0 0 18px;
  }

  .subtle {
    color: var(--muted);
    font-size: 13px;
  }

  .section {
    margin: 22px 0;
  }

  .section-title {
    font-size: 16px;
    font-weight: 700;
    margin: 0 0 12px;
  }

  .bottom-nav {
    position: fixed;
    left: 50%;
    bottom: 0;
    transform: translateX(-50%);
    width: 100%;
    max-width: 480px;
    height: 70px;
    padding: 8px 18px calc(8px + env(safe-area-inset-bottom));
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    background: rgba(247, 242, 234, 0.94);
    border-top: 1px solid var(--line);
    backdrop-filter: blur(12px);
    z-index: 20;
  }

  .nav-button {
    border: none;
    background: transparent;
    color: var(--muted);
    border-radius: 18px;
    font-size: 13px;
    font-weight: 600;
  }

  .nav-button.active {
    background: var(--soft);
    color: var(--ink);
  }

  .fab-button {
    position: fixed;
    right: max(18px, calc((100vw - 480px) / 2 + 18px));
    bottom: calc(82px + env(safe-area-inset-bottom));
    width: 56px;
    height: 56px;
    border-radius: 50%;
    border: none;
    background: var(--accent);
    color: #fff;
    font-size: 30px;
    line-height: 1;
    box-shadow: 0 8px 24px rgba(60, 40, 20, 0.25);
    z-index: 30;
  }

  .register-book-button {
  margin-top: 12px;
  padding: 10px 14px;
  border: none;
  border-radius: 12px;
  background: #d9cfc1;
  font-size: 14px;
}

  .book-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px 10px;
  }

  .book-card {
    min-width: 0;
  }

 .cover-wrap {
  position: relative;
  aspect-ratio: 0.68;
  border-radius: 7px;
  overflow: hidden;
  background: #e4d6c7;
  box-shadow: 0 5px 12px rgba(70, 45, 25, 0.16);
}

.book-cover {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.dummy-cover {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  padding: 8px 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #6d5b49;
  font-size: 12px;
  font-weight: 700;
  line-height: 1.35;
  background: linear-gradient(135deg, #efe1cf, #d8c3aa);
}

  .status-badge {
    position: absolute;
    top: 4px;
    right: 4px;
    width: 22px;
    height: 22px;
    display: grid;
    place-items: center;
    border-radius: 999px;
    background: rgba(255, 253, 248, 0.88);
    font-size: 13px;
  }

  .book-title {
    margin-top: 6px;
    font-size: 12px;
    line-height: 1.25;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .bookshelf-label-cover {
  aspect-ratio: 0.68;
  border-radius: 7px;
  background: #fffaf2;
  color: #8b6b47;
  border: 2px solid #d8c4ab;
  display: grid;
  place-items: center;
  text-align: center;
  font-size: 14px;
  font-weight: 800;
  line-height: 1.35;
  padding: 6px;
  word-break: break-word;
  overflow-wrap: anywhere;
}

  .horizontal-books {
    display: flex;
    gap: 12px;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  .horizontal-books .book-card {
    width: 78px;
    flex: 0 0 78px;
  }

  .detail-header {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin: -18px -16px 14px;
  padding: 10px 16px 8px;
  background: rgba(247, 242, 234, 0.96);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(229, 221, 210, 0.75);
}

  .icon-button {
    border: none;
    background: transparent;
    font-size: 20px;
    padding: 8px;
    border-radius: 999px;
  }

  .detail-cover {
    width: 132px;
    margin: 0 auto 14px;
  }

  .detail-title {
    text-align: center;
    font-size: 22px;
    font-weight: 800;
    margin: 0;
  }

  .detail-author {
    text-align: center;
    color: var(--muted);
    margin-top: 6px;
  }

  .genre-line {
    text-align: center;
    color: var(--muted);
    font-size: 13px;
    margin-top: 8px;
  }

  .archive-block {
    border-top: 1px solid var(--line);
    padding: 18px 0;
  }

  .archive-heading {
    font-size: 16px;
    font-weight: 800;
    margin-bottom: 8px;
  }

  .archive-meta {
    color: var(--muted);
    font-size: 13px;
    margin-bottom: 8px;
  }

  .archive-text {
    white-space: pre-wrap;
    line-height: 1.75;
    font-size: 15px;
  }

  .tag-line {
    border-top: 1px solid var(--line);
    padding-top: 18px;
    color: var(--muted);
    font-size: 13px;
  }

  .empty-message {
    color: var(--muted);
    padding: 32px 0;
    text-align: center;
  }

  .register-box,
  .other-box {
    background: var(--paper);
    border-radius: 22px;
    padding: 18px;
    border: 1px solid var(--line);
  }

  .input-row {
    display: flex;
    gap: 8px;
  }

  .text-input {
    width: 100%;
    border: 1px solid var(--line);
    border-radius: 16px;
    padding: 13px 14px;
    background: #fff;
  }

  .camera-button {
    border: none;
    border-radius: 16px;
    width: 50px;
    background: var(--soft);
  }

  .camera-preview {
  width: 100%;
  aspect-ratio: 4 / 3;
  border-radius: 18px;
  background: #000;
  object-fit: cover;
}

  .suggestion-list {
    margin-top: 16px;
  }

  .suggestion-item {
    padding: 12px 0;
    border-bottom: 1px solid var(--line);
  }

  .suggestion-title {
    font-weight: 700;
  }

  .create-button {
    width: 100%;
    margin-top: 18px;
    border: none;
    border-radius: 18px;
    padding: 14px;
    background: var(--accent);
    color: #fff;
    font-weight: 700;
  }

  .edit-form {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.edit-label {
  margin-top: 8px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.edit-input,
.edit-textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 13px 14px;
  background: var(--paper);
  color: var(--ink);
  outline: none;
}

.edit-textarea {
  resize: vertical;
  line-height: 1.7;
}

.edit-divider {
  height: 1px;
  background: var(--line);
  margin: 10px 0 8px;
}

.edit-sub-section {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 4px 0;
  border-bottom: 1px solid var(--line);
}

.edit-sub-title {
  font-size: 14px;
  font-weight: 700;
}

.mini-button {
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 999px;
  padding: 5px 10px;
  color: var(--ink);
  font-size: 13px;
}

.edit-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.rating-stars {
  display: flex;
  justify-content: center;
  gap: 10px;
  padding: 4px 0 2px;
}

.rating-star {
  border: none;
  background: transparent;
  color: var(--line);
  font-size: 25px;
  padding: 0 2px;
  
}

.rating-star.selected {
  color: var(--accent);
}

.genre-select-button {
  display: flex;
  align-items: center;
  justify-content: space-between;
  text-align: left;
}

.chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  min-height: 8px;
}

.input-chip {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink);
  border-radius: 999px;
  padding: 5px 8px 5px 10px;
  font-size: 13px;
  font-weight: 700;
}

.chip-remove {
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 0;
  font-size: 14px;
  line-height: 1;
}

.chip-suggestion-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  min-height: 0;
}

.chip-suggestion {
  border: 1px solid var(--line);
  background: var(--soft);
  color: var(--ink);
  border-radius: 999px;
  padding: 5px 9px;
  font-size: 12px;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(47, 42, 36, 0.28);
  z-index: 60;
  display: flex;
  align-items: flex-end;
  justify-content: center;
}

.modal-backdrop.hidden {
  display: none;
}

.bottom-nav.hidden,
.fab-button.hidden {
  display: none;
}

.bottom-sheet {
  width: 100%;
  max-width: 480px;
  max-height: 70vh;
  overflow-y: auto;
  background: var(--bg);
  border-radius: 24px 24px 0 0;
  padding: 16px 16px calc(20px + env(safe-area-inset-bottom));
}

.bottom-sheet-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.bottom-sheet-actions {
  display: flex;
  gap: 8px;
}

.bottom-sheet-title {
  font-weight: 800;
}

.genre-modal-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.bookshelf-filter-section {
  border-top: 1px solid var(--line);
  padding: 10px 0;
}

.bookshelf-filter-section-header {
  width: 100%;
  border: none;
  background: transparent;
  color: var(--ink);
  display: flex;
  gap: 8px;
  align-items: center;
  padding: 4px 0 10px;
  font-size: 14px;
  font-weight: 800;
  text-align: left;
}

.bookshelf-filter-section-body.hidden {
  display: none;
}

.genre-modal-chip {
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--muted);
  border-radius: 999px;
  padding: 9px 13px;
  font-size: 13px;
  font-weight: 700;
}

.genre-modal-chip.selected {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.home-split-section {
  display: grid;
  grid-template-columns: 1fr 86px;
  gap: 14px;
}

.home-split-section .horizontal-books {
  gap: 8px;
}

.home-split-section .horizontal-books .book-card {
  width: 72px;
  flex: 0 0 72px;
}

.on-this-day-card {
  width: 78px;
  flex: 0 0 78px;
}

.on-this-day-year {
  margin-top: 3px;
  color: var(--muted);
  font-size: 11px;
  text-align: center;
}

.isbn-result-card {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 12px;
  align-items: start;
  margin-top: 16px;
  padding: 12px 0;
  border-top: 1px solid var(--line);
}

.isbn-result-cover {
  position: relative;
  width: 72px;
  aspect-ratio: 0.68;
  border-radius: 7px;
  overflow: hidden;
  background: #e4d6c7;
}

.bookshelf-condition-card {
  background: #fff;
  border-radius: 16px;
  padding: 14px 16px;
  margin-bottom: 16px;
  cursor: pointer;
}

.bookshelf-condition-title {
  font-size: 16px;
  font-weight: 600;
}

.bookshelf-condition-summary {
  margin-top: 6px;
  font-size: 13px;
  color: #777;
}

.section-count {
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
  margin-left: 4px;
}