:root {
  --md-primary: #4B3B78;
  --md-on-primary: #FFFFFF;
  --md-primary-container: #E6DEFF;
  --md-on-primary-container: #200F4B;

  --md-secondary: #5F5A72;
  --md-on-secondary: #FFFFFF;
  --md-secondary-container: #E5DFF9;
  --md-on-secondary-container: #1B1730;

  --md-tertiary: #7C5265;
  --md-on-tertiary: #FFFFFF;
  --md-tertiary-container: #FFD9E6;
  --md-on-tertiary-container: #31101F;

  --md-error: #B3261E;
  --md-on-error: #FFFFFF;
  --md-error-container: #F9DEDC;
  --md-on-error-container: #410E0B;

  --md-background: #FFFBFF;
  --md-on-background: #1C1B1F;
  --md-surface: #FFFBFF;
  --md-on-surface: #1C1B1F;
  --md-surface-variant: #E7E0EC;
  --md-on-surface-variant: #49454E;
  --md-surface-container: #F3EDF7;
  --md-surface-container-high: #ECE6F0;

  --md-outline: #79747E;
  --md-outline-variant: #CAC4D0;

  --md-shadow-1: 0 1px 2px rgba(0, 0, 0, 0.14), 0 1px 3px 1px rgba(0, 0, 0, 0.08);
  --md-shadow-2: 0 1px 2px rgba(0, 0, 0, 0.16), 0 2px 6px 2px rgba(0, 0, 0, 0.10);

  --md-shape-sm: 8px;
  --md-shape-md: 12px;
  --md-shape-lg: 16px;
  --md-shape-full: 999px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --md-primary: #CFBDFF;
    --md-on-primary: #34215F;
    --md-primary-container: #4B3B78;
    --md-on-primary-container: #E6DEFF;

    --md-secondary: #C9C2DC;
    --md-on-secondary: #302B42;
    --md-secondary-container: #474259;
    --md-on-secondary-container: #E5DFF9;

    --md-tertiary: #EDB8CC;
    --md-on-tertiary: #48263A;
    --md-tertiary-container: #613850;
    --md-on-tertiary-container: #FFD9E6;

    --md-error: #F2B8B5;
    --md-on-error: #601410;
    --md-error-container: #8C1D18;
    --md-on-error-container: #F9DEDC;

    --md-background: #1C1B1F;
    --md-on-background: #E6E1E6;
    --md-surface: #1C1B1F;
    --md-on-surface: #E6E1E6;
    --md-surface-variant: #49454E;
    --md-on-surface-variant: #CAC4D0;
    --md-surface-container: #211F26;
    --md-surface-container-high: #2B2930;

    --md-outline: #948F99;
    --md-outline-variant: #49454E;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: 'Roboto', 'Noto Sans JP', system-ui, sans-serif;
  background: var(--md-background);
  color: var(--md-on-background);
  min-height: 100vh;
}

.app-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 8px;
  height: 64px;
  background: var(--md-surface);
  border-bottom: 1px solid var(--md-outline-variant);
  position: sticky;
  top: 0;
  z-index: 10;
}

.app-bar__icon-btn {
  width: 40px;
  height: 40px;
  border-radius: var(--md-shape-full);
  border: none;
  background: transparent;
  color: var(--md-on-surface-variant);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  cursor: pointer;
}
.app-bar__icon-btn:hover { background: var(--md-surface-container-high); }

.app-bar__title {
  font-size: 22px;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--md-on-surface);
  margin: 0;
}

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 24px 20px 96px;
}

h1 { font-size: 28px; font-weight: 500; margin: 0 0 8px; }
h2 { font-size: 20px; font-weight: 500; margin: 0 0 8px; }
p.supporting { font-size: 14px; color: var(--md-on-surface-variant); margin: 0 0 20px; line-height: 1.6; }

button {
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
}

.btn-filled {
  height: 40px;
  padding: 0 24px;
  border-radius: var(--md-shape-full);
  border: none;
  background: var(--md-primary);
  color: var(--md-on-primary);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
}
.btn-filled:active { opacity: 0.85; }

.btn-outlined {
  height: 40px;
  padding: 0 24px;
  border-radius: var(--md-shape-full);
  border: 1px solid var(--md-outline);
  background: transparent;
  color: var(--md-primary);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn-tonal {
  height: 40px;
  padding: 0 20px;
  border-radius: var(--md-shape-full);
  border: none;
  background: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn-text {
  height: 40px;
  padding: 0 12px;
  border-radius: var(--md-shape-full);
  border: none;
  background: transparent;
  color: var(--md-primary);
}

.btn-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--md-shape-full);
  border: none;
  background: transparent;
  color: var(--md-on-surface-variant);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
}
.btn-icon:hover { background: var(--md-surface-container-high); }

.field {
  position: relative;
  margin-bottom: 16px;
}
.field input, .field textarea {
  width: 100%;
  height: 56px;
  border-radius: var(--md-shape-sm);
  border: 1px solid var(--md-outline);
  background: transparent;
  color: var(--md-on-surface);
  padding: 0 16px;
  font-size: 16px;
  font-family: inherit;
}
.field input:focus, .field textarea:focus {
  outline: none;
  border: 2px solid var(--md-primary);
  padding: 0 15px;
}
.field label {
  display: block;
  font-size: 12px;
  color: var(--md-on-surface-variant);
  margin-bottom: 6px;
}

.card {
  background: var(--md-surface-container);
  border-radius: var(--md-shape-lg);
  padding: 16px;
  margin-bottom: 16px;
}
.card--elevated {
  background: var(--md-surface);
  box-shadow: var(--md-shadow-1);
}

.book-row {
  display: flex;
  gap: 12px;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid var(--md-outline-variant);
}
.book-row:last-child { border-bottom: none; }

.book-cover {
  width: 44px;
  height: 62px;
  border-radius: 4px;
  background: var(--md-surface-variant);
  object-fit: cover;
  flex-shrink: 0;
}

.book-info { flex: 1; min-width: 0; }
.book-title {
  font-size: 14px;
  font-weight: 500;
  margin: 0 0 2px;
  color: var(--md-on-surface);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.book-author {
  font-size: 12px;
  color: var(--md-on-surface-variant);
  margin: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  height: 32px;
  padding: 0 16px;
  border-radius: var(--md-shape-full);
  border: 1px solid var(--md-outline);
  background: transparent;
  color: var(--md-on-surface-variant);
  font-size: 13px;
}

.fab {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 56px;
  height: 56px;
  border-radius: var(--md-shape-lg);
  border: none;
  background: var(--md-primary-container);
  color: var(--md-on-primary-container);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  box-shadow: var(--md-shadow-2);
  cursor: pointer;
}

.empty-state {
  text-align: center;
  padding: 48px 16px;
  color: var(--md-on-surface-variant);
}
.empty-state i { font-size: 40px; margin-bottom: 12px; display: block; }

.snackbar {
  position: fixed;
  left: 50%;
  bottom: 24px;
  transform: translateX(-50%) translateY(80px);
  background: #313033;
  color: #F4EFF4;
  padding: 14px 20px;
  border-radius: var(--md-shape-sm);
  font-size: 14px;
  box-shadow: var(--md-shadow-2);
  transition: transform 0.2s ease;
  z-index: 20;
  max-width: 90vw;
  text-align: center;
}
.snackbar.show { transform: translateX(-50%) translateY(0); }

.divider { border: none; border-top: 1px solid var(--md-outline-variant); margin: 20px 0; }

.qr-wrap {
  display: flex;
  justify-content: center;
  padding: 20px;
  background: #FFFFFF;
  border-radius: var(--md-shape-lg);
  margin-bottom: 16px;
}

.row { display: flex; gap: 12px; }
.row > * { flex: 1; }

.spinner {
  width: 24px;
  height: 24px;
  border: 3px solid var(--md-outline-variant);
  border-top-color: var(--md-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 24px auto;
}
@keyframes spin { to { transform: rotate(360deg); } }

.app-bar__title-input {
  flex: 1;
  font-size: 20px;
  font-weight: 500;
  color: var(--md-on-surface);
  background: transparent;
  border: none;
  border-bottom: 2px solid var(--md-primary);
  padding: 0;
  font-family: inherit;
  min-width: 0;
}
.app-bar__title-input:focus { outline: none; }

video#scanner-preview {
  width: 100%;
  border-radius: var(--md-shape-lg);
  background: #000;
  margin-bottom: 16px;
}