:root {
  --bs-bg: #f4efe4;
  --bs-card: #fffdf8;
  --bs-border: #e6ddc6;
  --bs-divider: #efe7d4;
  --bs-ink: #2e2a22;
  --bs-text-2: #5c5344;
  --bs-muted: #8a8070;
  --bs-faint: #b7ad98;
  --bs-accent: #5f7a5a;
  --bs-accent-hover: #4c6448;
  --bs-accent-tint: #e7eee1;
  --bs-accent-line: #c7d6be;
  --bs-error: #b3392b;
  --bs-error-tint: #f6e6e3;
  --bs-shadow-card: 0 2px 10px rgba(60, 45, 20, 0.08);
  --bs-shadow-sheet: 0 -12px 40px rgba(40, 30, 10, 0.22);
  --bs-radius-card: 20px;
  --bs-radius-input: 12px;
  --bs-radius-pill: 999px;
  --bs-focus-ring: 0 0 0 3px rgba(95, 122, 90, 0.2);
  --bs-font-ui: "Nunito", sans-serif;
  --bs-font-title: "Lora", serif;
}

* {
  box-sizing: border-box;
}

/* [hidden] must always win over display:flex rules below (e.g. .sheet-overlay, .bottom-bar) */
[hidden] {
  display: none !important;
}

body {
  margin: 0;
  font-family: var(--bs-font-ui);
  background: var(--bs-bg);
  color: var(--bs-ink);
  padding-bottom: 100px;
}

button,
input,
textarea {
  font-family: inherit;
}

.brand-title {
  font-family: var(--bs-font-title);
  font-weight: 700;
  letter-spacing: 0.01em;
}

.muted {
  color: var(--bs-text-2);
}

/* ---- Auth gate ---- */

.auth-gate {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.auth-card {
  max-width: 420px;
  text-align: center;
  background: var(--bs-card);
  border-radius: var(--bs-radius-card);
  box-shadow: var(--bs-shadow-card);
  padding: 32px 24px;
}

.brand-icon {
  width: 48px;
  height: 48px;
  display: block;
  margin: 0 auto 12px;
}

.brand-icon-small {
  width: 28px;
  height: 28px;
  margin: 0;
  flex-shrink: 0;
}

.auth-card h1 {
  font-size: 30px;
  margin: 0 0 12px;
}

.auth-card p {
  color: var(--bs-text-2);
  line-height: 1.5;
  margin: 0 0 20px;
}

.auth-note {
  font-size: 12px;
  color: var(--bs-faint);
  margin-top: 16px !important;
}

/* ---- App shell ---- */

#app {
  max-width: 680px;
  margin: 0 auto;
  padding: 0 16px;
}

.app-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 20px 0 16px;
  position: sticky;
  top: 0;
  background: var(--bs-bg);
  z-index: 5;
}

.app-header h1 {
  flex: 1;
  font-size: 22px;
  margin: 0;
}

main {
  min-height: 40vh;
}

.view {
  animation: fade-in 180ms ease;
}

@keyframes fade-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

/* ---- Buttons ---- */

.btn {
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--bs-radius-pill);
  padding: 12px 22px;
  border: none;
  cursor: pointer;
  min-height: 44px;
  transition: background-color 150ms ease, color 150ms ease;
}

.btn:focus-visible {
  outline: none;
  box-shadow: var(--bs-focus-ring);
}

.btn-block {
  width: 100%;
  display: block;
}

.btn-primary {
  background: var(--bs-accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--bs-accent-hover);
}

.btn-primary:disabled {
  background: var(--bs-faint);
  cursor: not-allowed;
}

.btn-outline {
  background: var(--bs-card);
  color: var(--bs-accent-hover);
  border: 1.5px solid var(--bs-accent-line);
}

.btn-outline:hover {
  background: var(--bs-accent-tint);
}

.btn-danger-outline {
  color: var(--bs-error);
  border-color: #e3c3bb;
}

.btn-danger-outline:hover {
  background: var(--bs-error-tint);
}

.icon-btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: var(--bs-muted);
  font-size: 18px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.icon-btn:hover {
  background: var(--bs-accent-tint);
  color: var(--bs-accent-hover);
}

.icon-btn.delete-icon:hover {
  background: var(--bs-error-tint);
  color: var(--bs-error);
}

/* ---- Empty states ---- */

.empty-state {
  color: var(--bs-muted);
  text-align: center;
  padding: 48px 16px;
  line-height: 1.5;
}

.empty-illustration {
  width: 72px;
  height: 72px;
  display: block;
  margin: 0 auto 12px;
}

.how-it-works {
  text-align: left;
  max-width: 380px;
  margin: 28px auto 0;
}

.how-step {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  margin-bottom: 18px;
}

.how-step:last-child {
  margin-bottom: 0;
}

.how-icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  margin-top: 2px;
}

.how-step strong {
  display: block;
  color: var(--bs-ink);
  font-size: 14px;
}

.how-step p {
  margin: 2px 0 0;
  color: var(--bs-muted);
  font-size: 13px;
  line-height: 1.4;
}

.field-error {
  color: var(--bs-error);
  font-size: 13px;
  margin: 4px 0 0;
}

/* ---- Card list (tags / books) ---- */

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

.card-list li {
  background: var(--bs-card);
  border-radius: var(--bs-radius-card);
  box-shadow: var(--bs-shadow-card);
  margin-bottom: 16px;
  padding: 6px 6px 6px 22px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.card-open-btn {
  flex: 1;
  background: none;
  border: none;
  text-align: left;
  padding: 16px 0;
  cursor: pointer;
  font-family: inherit;
  color: inherit;
}

.card-open-btn .card-title {
  display: block;
  font-family: var(--bs-font-title);
  font-size: 18px;
  font-weight: 600;
  color: var(--bs-ink);
}

.card-open-btn .card-sub {
  display: block;
  font-size: 13px;
  color: var(--bs-muted);
  margin-top: 4px;
}

.card-actions {
  display: flex;
  gap: 2px;
}

/* ---- Book form ---- */

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-weight: 700;
  margin-bottom: 4px;
}

.form-group small {
  display: block;
  color: var(--bs-muted);
  font-size: 13px;
  margin-bottom: 10px;
}

input[type="text"],
input:not([type]),
textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid var(--bs-border);
  border-radius: var(--bs-radius-input);
  font-size: 16px;
  background: var(--bs-card);
  color: var(--bs-ink);
}

input:focus,
textarea:focus {
  outline: none;
  border-color: var(--bs-accent);
  box-shadow: var(--bs-focus-ring);
}

textarea {
  resize: vertical;
  line-height: 1.5;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 12px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: var(--bs-radius-pill);
  font-size: 13px;
  font-weight: 700;
  background: var(--bs-accent-tint);
  color: var(--bs-accent-hover);
  border: 1.5px solid transparent;
}

.chip-toggle {
  cursor: pointer;
  background: var(--bs-card);
  border: 1.5px solid var(--bs-accent-line);
  color: var(--bs-accent-hover);
}

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

.inline-add {
  display: flex;
  gap: 8px;
  margin-bottom: 8px;
}

.inline-add input {
  flex: 1;
}

/* ---- Book detail / pages ---- */

.book-meta {
  margin-bottom: 24px;
}

.book-meta h2 {
  font-family: var(--bs-font-title);
  font-size: 24px;
  margin: 0 0 4px;
}

.book-meta p {
  margin: 0 0 16px;
}

.page-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.page-card {
  background: var(--bs-card);
  border-radius: var(--bs-radius-input);
  box-shadow: var(--bs-shadow-card);
  overflow: hidden;
  cursor: pointer;
  border: none;
  padding: 0;
  text-align: left;
  display: block;
}

.page-card img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  display: block;
  background: var(--bs-divider);
}

.page-card .page-index {
  display: block;
  padding: 8px 10px;
  font-size: 12px;
  font-weight: 700;
  color: var(--bs-muted);
}

/* ---- Camera capture ---- */

.camera-wrap {
  position: relative;
  width: 100%;
  border-radius: var(--bs-radius-card);
  overflow: hidden;
  background: #1c1a15;
  min-height: 320px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

#newBookFields {
  margin-bottom: 4px;
}

.camera-video,
.capture-preview {
  width: 100%;
  max-height: 70vh;
  display: block;
  object-fit: contain;
}

.camera-fallback {
  margin: 16px;
}

.camera-wrap .field-error {
  color: #f2c9c1;
  text-align: center;
  padding: 24px;
}

/* ---- Bottom bars ---- */

.bottom-bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--bs-bg);
  border-top: 1px solid var(--bs-border);
  padding: 16px 20px calc(16px + env(safe-area-inset-bottom));
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  z-index: 10;
}

.review-bar {
  justify-content: space-between;
}

.review-bar .btn {
  flex: 1;
}

.shutter-btn {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: #fff;
  border: 4px solid var(--bs-accent);
  cursor: pointer;
}

.shutter-btn:active {
  background: var(--bs-accent-tint);
}

.fab {
  position: fixed;
  right: 20px;
  bottom: calc(20px + env(safe-area-inset-bottom));
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--bs-accent);
  color: #fff;
  border: none;
  font-size: 26px;
  font-weight: 700;
  box-shadow: 0 6px 18px rgba(60, 45, 20, 0.25);
  cursor: pointer;
  z-index: 10;
}

.fab:hover {
  background: var(--bs-accent-hover);
}

.fab-extended {
  width: auto;
  height: auto;
  padding: 14px 22px;
  border-radius: 999px;
  font-size: 16px;
  white-space: nowrap;
}

/* ---- Page detail ---- */

.page-detail-img {
  width: 100%;
  border-radius: var(--bs-radius-card);
  box-shadow: var(--bs-shadow-card);
  margin-bottom: 20px;
  display: block;
}

.save-hint {
  color: var(--bs-accent-hover);
  font-weight: 700;
  font-size: 13px;
}

/* ---- Bottom sheet ---- */

.sheet-overlay {
  position: fixed;
  inset: 0;
  background: rgba(46, 42, 34, 0.4);
  display: flex;
  align-items: flex-end;
  z-index: 20;
}

.sheet {
  width: 100%;
  max-height: 85vh;
  overflow-y: auto;
  background: var(--bs-bg);
  border-radius: 24px 24px 0 0;
  box-shadow: var(--bs-shadow-sheet);
  padding: 24px 20px calc(24px + env(safe-area-inset-bottom));
}

.sheet h3 {
  margin: 0 0 16px;
  font-family: var(--bs-font-title);
}

.sheet-actions {
  display: flex;
  gap: 12px;
}

.sheet-actions .btn {
  flex: 1;
}

.chip-row.wrap {
  margin-bottom: 16px;
}

@media (min-width: 480px) {
  .page-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}